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 1-6 of 6 results.

A269376 Permutation of nonnegative integers: a(1) = 0, a(2) = 1, a(2n) = 2*a(n), a(2n+1) = 1 + 2*a(A269370(2n+1)).

Original entry on oeis.org

0, 1, 3, 2, 5, 6, 7, 4, 15, 10, 13, 12, 31, 14, 63, 8, 9, 30, 11, 20, 127, 26, 21, 24, 255, 62, 23, 28, 25, 126, 511, 16, 1023, 18, 29, 60, 2047, 22, 27, 40, 17, 254, 4095, 52, 47, 42, 61, 48, 8191, 510, 16383, 124, 41, 46, 95, 56, 55, 50, 53, 252, 19, 1022, 32767, 32, 49, 2046, 65535, 36, 131071, 58, 125, 120
Offset: 1

Views

Author

Antti Karttunen, Mar 01 2016

Keywords

Comments

Note the indexing: Domain starts from 1, range from 0.

Crossrefs

Inverse: A269375.
Cf. A269370.
Related permutation: A269378.
Cf. also A252756, A269386.

Formula

a(1) = 0, a(2) = 1, a(2n) = 2*a(n), a(2n+1) = 1 + 2*a(A269370(2n+1)).
As a composition of related permutations:
a(n) = A269386(A260741(n)).

A269378 Permutation of natural numbers: a(1) = 0, after which a(2n) = 1 + 2*a(n), a(2n+1) = 2 * a(A269370(n)).

Original entry on oeis.org

0, 1, 2, 3, 6, 5, 4, 7, 8, 13, 10, 11, 16, 9, 32, 15, 14, 17, 12, 27, 64, 21, 26, 23, 128, 33, 24, 19, 22, 65, 256, 31, 512, 29, 18, 35, 1024, 25, 20, 55, 30, 129, 2048, 43, 48, 53, 34, 47, 4096, 257, 8192, 67, 54, 49, 96, 39, 40, 45, 42, 131, 28, 513, 16384, 63, 46, 1025, 32768, 59, 65536, 37, 66, 71, 131072, 2049, 262144, 51, 38, 41
Offset: 1

Views

Author

Antti Karttunen, Mar 01 2016

Keywords

Comments

Note the indexing: Domain starts from 1, range from 0.

Crossrefs

Inverse: A269377.
Cf. A269370.
Related permutation: A269376.
Cf. also A252754, A269388.

Formula

a(1) = 0, after which, a(2n) = 1 + 2*a(n), a(2n+1) = 2 * a(A269370(n)).
As a composition of related permutations:
a(n) = A269388(A260741(n)).

A270197 Self-inverse permutation of natural numbers: a(1) = 1, for n even, a(n) = A269369(1+a(n/2)), for n odd, a(n) = 2*a(A269370(n)-1).

Original entry on oeis.org

1, 3, 2, 5, 4, 7, 6, 11, 14, 19, 8, 17, 22, 9, 34, 29, 12, 21, 10, 53, 18, 13, 28, 47, 106, 81, 42, 23, 16, 123, 94, 83, 246, 15, 44, 59, 166, 39, 38, 155, 68, 27, 118, 35, 162, 103, 24, 137, 54, 375, 274, 239, 20, 49, 70, 65, 78, 61, 36, 365, 58, 333, 750, 245, 56, 403, 666, 41, 806, 55, 212, 173, 82, 585, 346, 113, 84, 57, 1170, 461, 26, 73, 32
Offset: 1

Views

Author

Antti Karttunen, Mar 13 2016

Keywords

Crossrefs

Similar or related permutations A270195, A270196, A269867.

Formula

a(1) = 1, for n even, a(n) = A269369(1+a(n/2)), for n odd, a(n) = 2*a(A269370(n)-1).

A269380 a(1) = 1, after which, for odd numbers: a(n) = A260739(n)-th number k for which A260738(k) = A260738(n)-1, and for even numbers: a(n) = a(n/2).

Original entry on oeis.org

1, 1, 2, 1, 3, 2, 5, 1, 4, 3, 7, 2, 11, 5, 6, 1, 13, 4, 9, 3, 8, 7, 17, 2, 23, 11, 10, 5, 25, 6, 19, 1, 12, 13, 15, 4, 29, 9, 14, 3, 37, 8, 41, 7, 16, 17, 43, 2, 21, 23, 18, 11, 47, 10, 31, 5, 20, 25, 35, 6, 53, 19, 22, 1, 27, 12, 61, 13, 24, 15, 67, 4, 55, 29, 26, 9, 71, 14, 33, 3, 28, 37, 77, 8, 49, 41, 30, 7, 83, 16, 89, 17, 32, 43, 39, 2
Offset: 1

Views

Author

Antti Karttunen, Mar 01 2016

Keywords

Comments

For odd numbers n > 1, a(n) tells which term is on the immediately preceding row of A255127 (square array generated by Ludic sieve), in the same column where n itself is.

Crossrefs

Cf. A269172, A269355, A269357, A269382, A269386, A269388 (sequences that use this function).
Cf. also A268674, A269370.

Formula

a(1) = 1; after which, for even numbers a(n) = a(n/2), and for odd numbers a(n) = A255127(A260738(n)-1, A260739(n)).
Other identities. For all n >= 1:
a(A269379(n)) = n.

A269369 a(1) = 1, a(n) = A260439(n)-th number k for which A260438(k) = A260438(n)+1; a(n) = A255551(A260438(n)+1, A260439(n)).

Original entry on oeis.org

1, 3, 7, 5, 19, 11, 9, 17, 13, 23, 39, 29, 15, 35, 21, 41, 61, 47, 27, 53, 25, 59, 81, 65, 31, 71, 45, 77, 103, 83, 33, 89, 37, 95, 123, 101, 43, 107, 57, 113, 145, 119, 49, 125, 55, 131, 165, 137, 51, 143, 63, 149, 187, 155, 85, 161, 97, 167, 207, 173, 91, 179, 67, 185, 229, 191, 69, 197, 73, 203, 249, 209, 75
Offset: 1

Views

Author

Antti Karttunen, Mar 01 2016

Keywords

Comments

For n > 1, a(n) = the number located immediately below n in A255551 (square array generated by Lucky sieve) in the same column where n itself is.
Permutation of odd numbers.

Crossrefs

Cf. A269370 (left inverse).
Cf. also A250469, A269379.

Programs

Formula

a(1) = 1; for n > 1, a(n) = A255551(A260438(n)+1, A260439(n)).
Other identities. For all n >= 1:
A269370(a(n)) = n.

A270196 Permutation of natural numbers: a(1) = 1, a(2n) = 2*a(n), a(A269369(1+n)) = 1 + 2*a(n).

Original entry on oeis.org

1, 2, 3, 4, 7, 6, 5, 8, 13, 14, 15, 12, 17, 10, 25, 16, 11, 26, 9, 28, 21, 30, 27, 24, 57, 34, 53, 20, 31, 50, 49, 32, 101, 22, 35, 52, 65, 18, 29, 56, 51, 42, 105, 60, 69, 54, 23, 48, 85, 114, 97, 68, 19, 106, 121, 40, 37, 62, 43, 100, 33, 98, 229, 64, 55, 202, 197, 44, 405, 70, 115, 104, 89, 130, 209, 36, 107, 58, 261, 112, 61
Offset: 1

Views

Author

Antti Karttunen, Mar 13 2016

Keywords

Crossrefs

Inverse: A270195.
Related or similar permutations: A269866, A269373, A269376, A270197.

Formula

a(1) = 1, after which for even n, a(n) = 2*a(n/2), for odd n, a(n) = 1 + 2*a(A269370(n)-1).
Showing 1-6 of 6 results.