Statement List for Metamath Proof Explorer - 4201-4300 - Page 43 of 107
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| Statement |
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| Theorem | omwordi 4201 |
Weak ordering property of ordinal multiplication.
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| Theorem | omwordri 4202 |
Weak ordering property of ordinal multiplication. Proposition 8.21 of
[TakeutiZaring] p. 63.
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| Theorem | omword1 4203 |
An ordinal is less than or equal to its product with another.
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| Theorem | omword2 4204 |
An ordinal is less than or equal to its product with another.
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| Theorem | om00 4205 |
The product of two ordinal numbers is zero iff at least one of them is
zero. Proposition 8.22 of [TakeutiZaring] p. 64.
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| Theorem | om00el 4206 |
The product of two nonzero ordinal numbers is nonzero.
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| Theorem | omordlim 4207 |
Ordering involving the product of a limit ordinal. Proposition 8.23 of
[TakeutiZaring] p. 64.
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| Theorem | omlimcl 4208 |
The product of any nonzero ordinal with a limit ordinal is a limit
ordinal. Proposition 8.24 of [TakeutiZaring] p. 64.
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| Theorem | odi 4209 |
Distributive law for ordinal arithmetic. Proposition 8.25 of
[TakeutiZaring] p. 64.
Warning: The HTML proof page is 3/4 megabyte
in size.
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| Theorem | omass 4210 |
Multiplication of ordinal numbers is associative. Theorem 8.26 of
[TakeutiZaring] p. 65.
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| Theorem | oneo 4211 |
If an ordinal number is even, its successor is odd.
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| Theorem | oen0 4212 |
Ordinal exponentiation with a nonzero mantissa is nonzero. Proposition
8.32 of [TakeutiZaring] p. 67.
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| Theorem | oeordi 4213 |
Ordering law for ordinal exponentiation. Proposition 8.33 of
[TakeutiZaring] p. 67.
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| Theorem | oeord 4214 |
Ordering property of ordinal exponentiation. Corollary 8.34 of
[TakeutiZaring] p. 68 and its
converse.
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| Theorem | oecan 4215 |
Left cancellation law for ordinal exponentiation.
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| Theorem | oeword 4216 |
Weak ordering property of ordinal exponentiation.
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| Theorem | oewordi 4217 |
Weak ordering property of ordinal exponentiation.
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| Theorem | oewordri 4218 |
Weak ordering property of ordinal exponentiation. Proposition 8.35 of
[TakeutiZaring] p. 68.
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| Theorem | oeworde 4219 |
Ordinal exponentiation compared to its exponent. Proposition 8.37 of
[TakeutiZaring] p. 68.
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| Theorem | oeordsuc 4220 |
Ordering property of ordinal exponentiation with a successor exponent.
Corollary 8.36 of [TakeutiZaring]
p. 68.
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| Theorem | oelim2 4221 |
Ordinal exponentiation with a limit exponent. Part of Exercise 4.36 of
[Mendelson] p. 250.
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| Natural number arithmetic |
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| Theorem | nna0 4222 |
Addition with zero. Theorem 4I(A1) of [Enderton] p. 79.
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| Theorem | nnm0 4223 |
Multiplication with zero. Theorem 4J(A1) of [Enderton] p. 80.
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| Theorem | nnasuc 4224 |
Addition with successor. Theorem 4I(A2) of [Enderton] p. 79.
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| Theorem | nnmsuc 4225 |
Multiplication with successor. Theorem 4J(A2) of [Enderton] p. 80.
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| Theorem | nna0r 4226 |
Addition to zero. Remark in proof of Theorem 4K(2) of [Enderton]
p. 81.
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| Theorem | nnm0r 4227 |
Multiplication with zero. Exercise 16 of [Enderton] p. 82.
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| Theorem | nnacl 4228 |
Closure of addition of natural numbers. Proposition 8.9 of
[TakeutiZaring] p. 59.
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| Theorem | nnmcl 4229 |
Closure of multiplication of natural numbers. Proposition 8.17 of
[TakeutiZaring] p. 63.
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| Theorem | nnecl 4230 |
Closure of exponentiation of natural numbers. Proposition 8.17 of
[TakeutiZaring] p. 63.
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| Theorem | nnarcl 4231 |
Reverse closure law for addition of natural numbers. Exercise 1 of
[TakeutiZaring] p. 62 and its
converse.
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| Theorem | nnacom 4232 |
Addition of natural numbers is commutative. Theorem 4K(2) of
[Enderton] p. 81.
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| Theorem | nnaordi 4233 |
Ordering property of addition. Proposition 8.4 of [TakeutiZaring] p. 58,
limited to natural numbers.
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| Theorem | nnaord 4234 |
Ordering property of addition. Proposition 8.4 of [TakeutiZaring] p. 58,
limited to natural numbers, and its converse.
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| Theorem | nnaordr 4235 |
Ordering property of addition of natural numbers.
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| Theorem | nnaass 4236 |
Addition of natural numbers is associative. (For brevity, this is just a
special case of the proof for ordinals. A direct proof would be about 1/3
the size of the ordinal proof, since it would use finite induction and not
require the limit ordinal case..) Theorem 4K(1) of [Enderton] p. 81.
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| Theorem | nndi 4237 |
Distributive law for natural numbers. (For brevity, this is just a
special case of the proof for ordinals. A direct proof would be about 1/4
the size of the ordinal proof, since it would use finite induction and not
require the limit ordinal case.) Theorem 4K(3) of [Enderton] p. 81.
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| Theorem | nnmass 4238 |
Multiplication of natural numbers is associative. (For brevity, this is
just a special case of the proof for ordinals. A direct proof would be
about 1/3 the size of the ordinal proof, since it would use finite
induction and not require the limit ordinal case..) Theorem 4K(4) of
[Enderton] p. 81.
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| Theorem | nnmsucr 4239 |
Multiplication with successor. Exercise 16 of [Enderton] p. 82.
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| Theorem | nnmcom 4240 |
Multiplication of natural numbers is commutative. Theorem 4K(5) of
[Enderton] p. 81.
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| Theorem | nnacan 4241 |
Cancellation law for addition of natural numbers.
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| Theorem | nnaword 4242 |
Weak ordering property of addition.
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| Theorem | nnaword1 4243 |
Weak ordering property of addition.
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| Theorem | nnaword2 4244 |
Weak ordering property of addition.
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| Theorem | nnmordi 4245 |
Ordering property of multiplication. Half of Proposition 8.19 of
[TakeutiZaring] p. 63, limited to
natural numbers.
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| Theorem | nnmord 4246 |
Ordering property of multiplication. Proposition 8.19 of
[TakeutiZaring] p. 63, limited to
natural numbers.
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| Theorem | nnmcan 4247 |
Cancellation law for multiplication of natural numbers.
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| Theorem | nnaordex 4248 |
Equivalence for ordering. Compare Exercise 23 of [Enderton] p. 88.
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| Theorem | nnawordex 4249 |
Equivalence for weak ordering of natural numbers.
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| Theorem | oaabslem 4250 |
Lemma for oaabs 4251.
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| Theorem | oaabs 4251 |
Ordinal addition absorbs a natural number added to the left of a
transfinite number. Proposition 8.10 of [TakeutiZaring] p. 59.
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| Theorem | 1onn 4252 |
One is a natural number.
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| Theorem | 2onn 4253 |
The ordinal 2 is a natural number.
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| Theorem | nneob 4254 |
A natural number is even iff its successor is odd.
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| Theorem | omsmolem 4255 |
Lemma for omsmo 4256.
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| Theorem | omsmo 4256 |
A strictly monotonic ordinal function on the set of natural numbers
is one-to-one.
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