cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A126004 A106486-encodings of combinatorial games whose value is greater than zero.

Original entry on oeis.org

1, 4, 5, 9, 12, 13, 17, 20, 21, 25, 28, 29, 65, 68, 69, 73, 76, 77, 81, 84, 85, 89, 92, 93, 129, 132, 133, 137, 140, 141, 145, 148, 149, 153, 156, 157, 193, 196, 197, 201, 204, 205, 209, 212, 213, 217, 220, 221, 256, 257, 260, 261, 264, 265, 268, 269, 272, 273
Offset: 1

Views

Author

Antti Karttunen, Dec 18 2006

Keywords

Comments

In these games, the left can always win.

Crossrefs

Intersection of complement of A126002 and A126001. Cf. A125991, A126001-A126003.

A126012 A106486-encoding of the canonical representative of the combinatorial game with code n.

Original entry on oeis.org

0, 1, 2, 3, 4, 4, 6, 6, 0, 9, 2, 3, 12, 12, 6, 6, 0, 1, 18, 3, 4, 4, 6, 6, 0, 9, 18, 3, 12, 12, 6, 6, 32, 33, 32, 33, 36, 36, 36, 36, 32, 33, 32, 33, 36, 36, 36, 36, 48, 33, 48, 33, 36, 36, 36, 36, 48, 33, 48, 33, 36, 36, 36, 36, 0, 1, 66, 67, 4, 4, 6, 6, 0, 9, 66, 67, 12, 12, 6, 6
Offset: 0

Views

Author

Antti Karttunen, Dec 18 2006

Keywords

Examples

			25 (= 2^(2*2) + 2^(2*0) + 2^(1+2*1)) encodes the game {-1,0|1}, where, as the option -1 is dominated by option 0, the former can be deleted, giving us the game {0|1}, i.e. the canonical (minimal) form of the game 1/2, encoded as 2^(2*0) + 2^(1+2*1) = 9, thus a(25)=9 and a(9)=9. Similarly a(65536)=1, as 65536 (= 2^(2*(2^(1+2*1)))) encodes the game {{|1}|}, which is reversible to the game {0|}, i.e. the game 1, which is encoded as 2^(2*0) = 1.
		

Crossrefs

A126011 gives the distinct terms (and also the records).

A126013 Inverse function of N->N injection A126011.

Original entry on oeis.org

0, 1, 2, 3, 4, 0, 5, 0, 0, 6, 0, 0, 7, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, 10, 0, 0, 11, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 13, 14, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15, 16, 0, 0
Offset: 0

Views

Author

Antti Karttunen, Dec 18 2006

Keywords

Comments

a(0)=0 because A126011(0)=0, but a(n) = 0 also for those n which do not occur as values of A126011. All positive natural numbers occur here once.

Crossrefs

a(A126011(n)) = n for all n.

A125992 A106486-encodings of combinatorial games with value 1.

Original entry on oeis.org

1, 17, 65, 81, 513, 529, 577, 593, 2049, 2065, 2113, 2129, 2561, 2577, 2625, 2641, 4097, 4113, 4161, 4177, 4609, 4625, 4673, 4689, 6145, 6161, 6209, 6225, 6657, 6673, 6721, 6737, 8193, 8209, 8257, 8273, 8705, 8721, 8769, 8785, 10241, 10257
Offset: 1

Views

Author

Antti Karttunen, Dec 18 2006

Keywords

Comments

These are codes for games which belong to the same equivalence class as the game {0|} (i.e. game 1).

Examples

			Game {0|} is encoded as 2^(2*0) = 1, thus 1 is the first term of this sequence. Also 17 belongs into this sequence, as it encodes game {-1,0|}, where, as the option -1 is dominated by option 0, the former can be deleted, resulting the same game {0|}. Also code 65536 (= 2^(2*(2^(1+2*1)))) belongs into this sequence, as it encodes the game {{|1}|}, which is reversible to game 1.
		

Crossrefs

Row 2 of A126000.

A125993 A106486-encodings of combinatorial games with value -1.

Original entry on oeis.org

2, 10, 130, 138, 514, 522, 642, 650, 2050, 2058, 2178, 2186, 2562, 2570, 2690, 2698, 8194, 8202, 8322, 8330, 8706, 8714, 8834, 8842, 10242, 10250, 10370, 10378, 10754, 10762, 10882, 10890, 32770, 32778, 32898, 32906, 33282, 33290, 33410
Offset: 1

Views

Author

Antti Karttunen, Dec 18 2006

Keywords

Comments

These are codes for games which belong to the same equivalence class as the game {|0} (i.e. game -1).

Examples

			Game {|0} is encoded as 2^(1+2*0) = 2, thus 2 is the first term of this sequence. Also 10 belongs belongs into this sequence, as it encodes game {|0,1}, where, as the option 0 dominates the option 1, the latter can be deleted, resulting the same game {|0}. Likewise code 8589934592 (= 2^(1+(2*2^(2*2)))) belongs into this sequence, as it encodes the game {|{-1|}}, which is reversible to game -1.
		

Crossrefs

Row 3 of A126000.

A125995 A106486-encodings of combinatorial games with value 2.

Original entry on oeis.org

4, 5, 20, 21, 68, 69, 84, 85, 4100, 4101, 4116, 4117, 4164, 4165, 4180, 4181, 16388, 16389, 16404, 16405, 16452, 16453, 16468, 16469, 20484, 20485, 20500, 20501, 20548, 20549, 20564, 20565, 65540, 65541, 65556, 65557, 65604, 65605, 65620
Offset: 1

Views

Author

Antti Karttunen, Dec 18 2006

Keywords

Comments

These are codes for games which belong to the same equivalence class as the game {1|} (i.e. the game 2).

Examples

			Game {1|} is encoded as 2^(2*1) = 4, thus 4 is the first term of this sequence. Also 5 belongs into this sequence, as it encodes game {0,1|}, where, because the option 1 dominates the option 0 on the left side, the zero can be deleted, resulting the same game {1|}.
		

Crossrefs

Row 5 of A126000.

A125996 A106486-encodings of combinatorial games equivalent to game {1|0}.

Original entry on oeis.org

6, 7, 14, 15, 22, 23, 30, 31, 70, 71, 78, 79, 86, 87, 94, 95, 518, 519, 526, 527, 534, 535, 542, 543, 582, 583, 590, 591, 598, 599, 606, 607, 2054, 2055, 2062, 2063, 2070, 2071, 2078, 2079, 2118, 2119, 2126, 2127, 2134, 2135, 2142, 2143, 2566, 2567
Offset: 1

Views

Author

Antti Karttunen, Dec 18 2006

Keywords

Comments

These are codes for games which belong to the same equivalence class as the game {1|0}.

Examples

			Game {1|0} is encoded as 2^(2*1) + 2^(1+2*0) = 6, thus 6 is the first term of this sequence. Also 7 belongs into this sequence, as it encodes game {0,1|0}, where, as the option 1 dominates the option 0 on the left side, the former can be deleted, resulting the same game {1|0}.
		

Crossrefs

Row 6 of A126000.

A125997 A106486-encodings of combinatorial games equivalent to game {0|1}.

Original entry on oeis.org

9, 25, 73, 89, 521, 537, 585, 601, 2057, 2073, 2121, 2137, 2569, 2585, 2633, 2649, 4105, 4121, 4169, 4185, 4617, 4633, 4681, 4697, 6153, 6169, 6217, 6233, 6665, 6681, 6729, 6745, 8201, 8217, 8265, 8281, 8713, 8729, 8777, 8793, 10249, 10265
Offset: 1

Views

Author

Antti Karttunen, Dec 18 2006

Keywords

Comments

These are codes for games which belong to the same equivalence class as the game {0|1} (game 1/2).

Examples

			Game {0|1} is encoded as 2^(2*0) + 2^(1+2*1) = 9, thus 9 is the first term of this sequence. Also 25 (= 2^(2*2) + 2^(2*0) + 2^(1+2*1)) belongs into this sequence, as it encodes game {-1,0|1}, where, as the option -1 is dominated by option 0, the former can be deleted, resulting the same game {0|1}.
		

Crossrefs

Row 7 of A126000.

A125998 A106486-encodings of combinatorial games equivalent to game {1|1}.

Original entry on oeis.org

12, 13, 28, 29, 76, 77, 92, 93, 524, 525, 540, 541, 588, 589, 604, 605, 2060, 2061, 2076, 2077, 2124, 2125, 2140, 2141, 2572, 2573, 2588, 2589, 2636, 2637, 2652, 2653, 4108, 4109, 4124, 4125, 4172, 4173, 4188, 4189, 4620, 4621, 4636, 4637
Offset: 1

Views

Author

Antti Karttunen, Dec 18 2006

Keywords

Comments

These are codes for games which belong to the same equivalence class as the game {1|1}, the impartial game 1*.

Examples

			Game {1|1} is encoded as 2^(2*1) + 2^(1+2*1) = 12, thus 12 is the first term of this sequence. Also 13 belongs into this sequence, as it encodes game {0,1|1}, where, as the option 0 is dominated by option 1, the former can be deleted, resulting the same game {1|1}.
		

Crossrefs

Row 8 of A126000.

A126009 Self-inverse permutation of integers induced when A106485 is restricted to A126011.

Original entry on oeis.org

0, 2, 1, 3, 9, 10, 8, 12, 6, 4, 5, 11, 7, 17, 18, 19, 20, 13, 14, 15, 16, 21
Offset: 0

Views

Author

Antti Karttunen, Jan 02 2007

Keywords

Comments

The Scheme-program given cannot in practice compute this further than n=21, as A106485(A126011(22))=36893488147419103232. However, the further terms could be deduced by other means. This sequence is a permutation of the nonnegative integers because combinatorial games form a group under (game) addition and each game has a well-defined, unique negative.

Formula

a(n) = A126013(A106485(A126011(n))).

Extensions

Typos corrected by Franklin T. Adams-Watters, Apr 06 2009
Previous Showing 11-20 of 20 results.