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.

Showing 1-3 of 3 results.

A269863 Permutation of natural numbers: a(1) = 1, a(A269360(n)) = 2*a(n), a(A250469(1+n)) = 1 + 2*a(n).

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 9, 10, 7, 8, 13, 18, 17, 26, 11, 12, 37, 34, 25, 74, 19, 20, 69, 50, 21, 14, 15, 16, 41, 138, 33, 82, 27, 36, 53, 22, 277, 66, 35, 52, 45, 554, 105, 90, 23, 24, 1109, 210, 101, 42, 75, 68, 49, 2218, 149, 38, 51, 148, 137, 98, 297, 274, 39, 40, 29, 30, 197, 594, 139, 100, 61, 394, 201, 122, 43, 28, 73, 106, 789, 402, 31, 32
Offset: 1

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Author

Antti Karttunen, Mar 13 2016

Keywords

Links

Crossrefs

Inverse: A269864.
Cf. A250469, A268674, A269360.
Differs from similarly constructed A245605 for the first time at n=21, where a(21)=19, instead of 15.

Formula

a(1) = 1, after which for even n, a(n) = 2*a(A268674(n-1)), for odd n, a(n) = 1 + 2*a(A268674(n)-1).

A269864 Permutation of natural numbers: a(1) = 1, a(2n) = A269360(a(n)), a(2n+1) = A250469(1+a(n)).

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 9, 10, 7, 8, 15, 16, 11, 26, 27, 28, 13, 12, 21, 22, 25, 36, 45, 46, 19, 14, 33, 76, 65, 66, 81, 82, 31, 18, 39, 34, 17, 56, 63, 64, 29, 50, 75, 106, 41, 116, 135, 136, 53, 24, 57, 40, 35, 86, 99, 226, 143, 120, 195, 196, 71, 206, 243, 244, 89, 38, 93, 52, 23, 96, 117, 100, 77, 20, 51, 166, 145, 156, 189, 190, 119, 32, 87
Offset: 1

Views

Author

Antti Karttunen, Mar 13 2016

Keywords

Comments

This sequence can be represented as a binary tree. When the parent contains n, the left hand child contains A269360(n) [= 1+A250469(n)] and the right hand child contains A250469(1+n):
1
|
................../ \..................
2 3
4......../ \........5 6......../ \........9
/ \ / \ / \ / \
/ \ / \ / \ / \
/ \ / \ / \ / \
10 7 8 15 16 11 26 27
28 13 12 21 22 25 36 45 46 19 14 33 76 65 66 81
etc.

Links

Crossrefs

Inverse: A269863.
Cf. A250469, A269360.
Cf. also A269865, A269866, A269867.
Differs from similarly constructed A245606 for the first time at n=15, where a(15)=27 instead of 21.

Formula

a(1) = 1, a(2n) = 1 + A250469(a(n)), a(2n+1) = A250469(1+a(n)).

A269359 Self-inverse permutation of natural numbers: a(1)=1, a(A269360(n)) = A250469(1+a(n)), a(A250469(1+n)) = A269360(a(n)).

Original entry on oeis.org

1, 3, 2, 9, 6, 5, 26, 11, 4, 27, 8, 65, 66, 25, 16, 15, 120, 71, 36, 169, 76, 33, 74, 41, 14, 7, 10, 81, 86, 185, 206, 215, 22, 195, 50, 19, 330, 515, 196, 75, 24, 337, 186, 49, 46, 45, 348, 247, 44, 35, 358, 213, 116, 353, 290, 143, 106, 507, 536, 295, 1266, 1345, 226, 99, 12, 13, 512, 2321, 220, 123, 18, 1285, 306, 23, 40, 21
Offset: 1

Views

Author

Antti Karttunen, Mar 13 2016

Keywords

Links

Crossrefs

Cf. A250469, A268674, A269360.
Similar or related permutations: A244319, A269863, A269864, A269865, A269866, A269867.

Formula

a(1) = 1, after which for even n, a(n) = A250469(1+a(A268674(n-1))), for odd n, a(n) = A269360(a(A268674(n)-1)).
The declarative form can be expressed in terms of A250469 only:
a(1)=1, a(1+A250469(n)) = A250469(1+a(n)), a(A250469(1+n)) = 1+A250469(a(n)).
Showing 1-3 of 3 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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