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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A265330 Zero-based row index to A265345; 2-adic valuation of bijective base-3 reversal of n: a(n) = A007814(A263273(n)).

Original entry on oeis.org

0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 6, 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 3
Offset: 1

Views

Author

Antti Karttunen, Dec 18 2015

Keywords

Examples

			For n = 32, in base-3 "1012" [= A007089(32)], when we reverse it, we get "2101" [= A007089(64)], and 2-adic valuation of 64 [= "1000000" = A007088(64)] is 6, thus a(32) = 6.
		

Crossrefs

One less than A265331.
Cf. A265910 (corresponding other index).
Cf. also A265336, A265337, A265340.
Differs from A007814 for the first time at n=32, where a(32) = 6, while A007814(32) = 5.

Formula

a(n) = A007814(A263273(n)).
a(2n+1) = 0, a(2n) = 1 + a(A265352(n)).

A265336 Number of nonleading 0-bits in bijective base-3 reversal of n: a(n) = A080791(A263273(n)).

Original entry on oeis.org

0, 0, 1, 0, 2, 0, 1, 1, 3, 2, 2, 2, 2, 1, 2, 2, 4, 2, 3, 1, 3, 0, 1, 1, 3, 3, 2, 1, 2, 1, 1, 3, 6, 2, 2, 4, 4, 0, 2, 2, 4, 4, 5, 3, 4, 0, 4, 1, 4, 2, 4, 3, 3, 2, 2, 1, 3, 4, 3, 5, 2, 1, 4, 2, 5, 1, 3, 3, 5, 4, 3, 3, 5, 3, 1, 2, 3, 3, 3, 2, 5, 4, 4, 4, 4, 2, 2, 4, 6, 3, 3, 2, 4, 1, 2, 3, 6, 5, 4, 3, 4, 3, 5, 0, 5, 2, 4, 2, 3, 3, 4, 2, 4, 5, 3, 4, 3, 2, 2, 2, 3, 2, 4, 4, 5, 3, 4, 2, 4
Offset: 0

Views

Author

Antti Karttunen, Dec 18 2015

Keywords

Crossrefs

Formula

a(n) = A080791(A263273(n)).
a(0) = 0, a(2n) = 1 + a(A265339(n)), a(2n+1) = a(A265339(n)).
a(n) = A265340(n) - A265337(n).

A265337 Number of 1-bits in base-3 reversal of n: a(n) = A000120(A263273(n)).

Original entry on oeis.org

0, 1, 1, 2, 1, 3, 2, 2, 1, 2, 2, 3, 2, 3, 3, 3, 1, 3, 2, 3, 2, 4, 3, 4, 2, 2, 3, 4, 3, 5, 4, 3, 1, 4, 4, 3, 2, 5, 4, 4, 2, 3, 2, 3, 3, 6, 2, 5, 2, 4, 3, 4, 3, 5, 4, 4, 3, 2, 3, 2, 4, 5, 3, 4, 1, 5, 3, 3, 2, 3, 3, 4, 2, 3, 5, 4, 3, 4, 4, 4, 2, 3, 3, 4, 3, 5, 6, 4, 2, 5, 4, 5, 4, 6, 5, 5, 2, 3, 4, 5, 3, 5, 3, 7, 3, 6, 4, 6, 4, 4, 4, 5, 3, 3, 5, 4, 5, 5, 5, 6, 4, 5, 4, 4, 3, 5, 4, 5, 4
Offset: 0

Views

Author

Antti Karttunen, Dec 18 2015

Keywords

Crossrefs

Programs

Formula

a(n) = A000120(A263273(n)).
a(0) = 0, a(2n) = a(A265339(n)), a(2n+1) = 1 + a(A265339(n)).
a(n) = A265340(n) - A265336(n).

A265339 a(n) = A263273(A004526(A263273(n))).

Original entry on oeis.org

0, 0, 1, 1, 2, 3, 3, 2, 4, 4, 7, 9, 6, 6, 19, 10, 8, 12, 9, 7, 10, 5, 5, 19, 12, 8, 13, 13, 22, 27, 21, 18, 64, 28, 23, 36, 18, 21, 55, 11, 20, 57, 57, 24, 58, 37, 25, 30, 24, 15, 73, 31, 26, 39, 27, 22, 28, 16, 11, 64, 30, 23, 31, 14, 16, 55, 15, 20, 46, 46, 17, 58, 36, 25, 37, 17, 14, 73, 39, 26, 40, 40
Offset: 0

Views

Author

Antti Karttunen, Dec 18 2015

Keywords

Comments

When permutation A263273 is viewed as a binary tree, a(n) gives the parent node of node containing n, for all n >= 1.
Each n occurs exactly twice in the sequence.

Crossrefs

Programs

Formula

a(n) = A263273(A004526(A263273(n))).

A265363 Permutation of nonnegative integers: a(n) = A264974(A263273(n)).

Original entry on oeis.org

0, 1, 2, 3, 4, 7, 6, 5, 16, 9, 10, 11, 12, 13, 34, 21, 8, 25, 18, 19, 20, 15, 14, 43, 48, 17, 52, 27, 28, 29, 30, 31, 88, 33, 32, 97, 36, 37, 38, 39, 40, 115, 102, 35, 106, 63, 22, 61, 24, 23, 70, 75, 26, 79, 54, 55, 56, 57, 58, 169, 60, 59, 178, 45, 46, 47, 42, 41, 124, 129, 44, 133, 144, 49, 142, 51, 50, 151, 156, 53, 160, 81
Offset: 0

Views

Author

Antti Karttunen, Dec 07 2015

Keywords

Comments

Composition of A263273 with the permutation obtained from its quadrisection.

Crossrefs

Inverse: A265364.
Cf. also A265343, A265365.

Programs

Formula

a(n) = A264974(A263273(n)).
Other identities. For all n >= 0:
a(3*n) = 3*a(n).

A265364 Permutation of nonnegative integers: a(n) = A263273(A264974(n)).

Original entry on oeis.org

0, 1, 2, 3, 4, 7, 6, 5, 16, 9, 10, 11, 12, 13, 22, 21, 8, 25, 18, 19, 20, 15, 46, 49, 48, 17, 52, 27, 28, 29, 30, 31, 34, 33, 14, 43, 36, 37, 38, 39, 40, 67, 66, 23, 70, 63, 64, 65, 24, 73, 76, 75, 26, 79, 54, 55, 56, 57, 58, 61, 60, 47, 142, 45, 136, 137, 138, 139, 148, 147, 50, 151, 144, 145, 146, 51, 154, 157, 156, 53, 160, 81
Offset: 0

Views

Author

Antti Karttunen, Dec 07 2015

Keywords

Comments

Composition of A263273 with the permutation obtained from its quadrisection.

Crossrefs

Inverse: A265363.
Cf. also A265344, A265366.

Programs

Formula

a(n) = A263273(A264974(n)).
Other identities. For all n >= 0:
a(3*n) = 3*a(n).

A266407 Permutation of natural numbers: a(n) = A064989(A263273((2*n)-1)).

Original entry on oeis.org

1, 2, 5, 3, 4, 17, 11, 10, 9, 7, 6, 19, 13, 8, 21, 31, 34, 71, 29, 22, 61, 25, 20, 59, 41, 18, 73, 23, 14, 33, 43, 12, 53, 37, 38, 35, 15, 26, 67, 47, 16, 157, 107, 42, 145, 55, 62, 197, 69, 68, 179, 113, 142, 129, 39, 58, 191, 137, 44, 45, 49, 122, 227, 101, 50, 199, 151, 40, 121, 57, 118, 211, 89, 82, 111, 149, 36, 91, 85
Offset: 1

Views

Author

Antti Karttunen, Jan 02 2016

Keywords

Crossrefs

Inverse: A266408.
Cf. also A064216, A266401, A266403.

Programs

  • PARI
    A030102(n) = { my(r=[n%3]); while(0M. F. Hasler's Nov 04 2011 code in A030102.
    A263273 = n -> if(!n,n,A030102(n/(3^valuation(n,3))) * (3^valuation(n, 3))); \\ Taking of the quotient probably unnecessary.
    A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
    A266407 = n -> A064989(A263273((2*n)-1));
    for(n=1, 9842, write("b266407.txt", n, " ", A266407(n)));
    
  • Scheme
    (define (A266407 n) (A064989 (A263273 (+ n n -1))))

Formula

a(n) = A064989(A263273((2*n)-1)).

A266408 Permutation of natural numbers: a(n) = (1/2) * (1+A263273(A003961(n))).

Original entry on oeis.org

1, 2, 4, 5, 3, 11, 10, 14, 9, 8, 7, 32, 13, 29, 37, 41, 6, 26, 12, 23, 15, 20, 28, 95, 22, 38, 115, 86, 19, 110, 16, 122, 30, 17, 36, 77, 34, 35, 55, 68, 25, 44, 31, 59, 60, 83, 40, 284, 61, 65, 100, 113, 33, 344, 46, 257, 70, 56, 24, 329, 21, 47, 289, 365, 88, 89, 39, 50, 49, 107, 18, 230, 27, 101, 244, 104, 112, 164, 82, 203, 174, 74
Offset: 1

Views

Author

Antti Karttunen, Jan 02 2016

Keywords

Crossrefs

Inverse: A266407.
Cf. also A048673, A266401, A266403.

Programs

  • PARI
    A030102(n) = { my(r=[n%3]); while(0M. F. Hasler's Nov 04 2011 code in A030102.
    A263273 = n -> if(!n,n,A030102(n/(3^valuation(n,3))) * (3^valuation(n, 3))); \\ Taking of the quotient probably unnecessary.
    A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ Using code of Michel Marcus
    A266408 = n -> (1+A263273(A003961(n)))/2;
    for(n=1, 8191, write("b266408.txt", n, " ", A266408(n)));
    
  • Scheme
    (define (A266408 n) (/ (+ 1 (A263273 (A003961 n))) 2))

Formula

a(n) = (1/2) * (1+A263273(A003961(n))).

A265365 Permutation of nonnegative integers: a(n) = A264978(A263273(n)).

Original entry on oeis.org

0, 1, 2, 3, 8, 7, 6, 5, 4, 9, 10, 29, 24, 26, 25, 21, 23, 22, 18, 17, 20, 15, 14, 16, 12, 11, 13, 27, 28, 83, 30, 89, 88, 87, 86, 85, 72, 71, 74, 78, 80, 79, 75, 77, 76, 63, 62, 61, 69, 68, 70, 66, 65, 67, 54, 19, 56, 51, 53, 52, 60, 59, 58, 45, 44, 47, 42, 41, 43, 48, 50, 49, 36, 35, 34, 33, 32, 31, 39, 38, 40, 81
Offset: 0

Views

Author

Antti Karttunen, Dec 07 2015

Keywords

Comments

Composition of A263273 with the permutation obtained from its octisection.

Crossrefs

Inverse: A265366.
Cf. also A265363.

Programs

Formula

a(n) = A264978(A263273(n)).
Other identities. For all n >= 0:
a(3*n) = 3*a(n).

A265366 Permutation of nonnegative integers: a(n) = A263273(A264978(n)).

Original entry on oeis.org

0, 1, 2, 3, 8, 7, 6, 5, 4, 9, 10, 25, 24, 26, 22, 21, 23, 19, 18, 55, 20, 15, 17, 16, 12, 14, 13, 27, 28, 11, 30, 77, 76, 75, 74, 73, 72, 217, 79, 78, 80, 67, 66, 68, 64, 63, 190, 65, 69, 71, 70, 57, 59, 58, 54, 163, 56, 165, 62, 61, 60, 47, 46, 45, 136, 52, 51, 53, 49, 48, 50, 37, 36, 109, 38, 42, 44, 43, 39, 41, 40, 81
Offset: 0

Views

Author

Antti Karttunen, Dec 07 2015

Keywords

Comments

Composition of A263273 with the permutation obtained from its octisection.

Crossrefs

Inverse: A265365.
Cf. also A265364.

Programs

Formula

a(n) = A263273(A264978(n)).
Other identities. For all n >= 0:
a(3*n) = 3*a(n).
Previous Showing 21-30 of 70 results. Next