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 1-10 of 10 results.

A270425 Permutation of natural numbers: a(1) = 1, a(2n) = 2*a(n), a(2n+1) = 1 + 2*a(A265354(n)).

Original entry on oeis.org

1, 2, 3, 4, 7, 6, 5, 8, 9, 14, 19, 12, 13, 10, 29, 16, 25, 18, 11, 28, 15, 38, 23, 24, 17, 26, 27, 20, 55, 58, 37, 32, 41, 50, 73, 36, 31, 22, 39, 56, 67, 30, 49, 76, 63, 46, 117, 48, 59, 34, 75, 52, 79, 54, 77, 40, 33, 110, 129, 116, 47, 74, 21, 64, 155, 82, 57, 100, 93, 146, 221, 72, 35, 62, 51, 44, 71, 78, 53, 112, 113, 134, 227, 60
Offset: 1

Views

Author

Antti Karttunen, Mar 17 2016

Keywords

Crossrefs

Inverse: A270426.
Cf. A265354.

Formula

a(1) = 1, a(2n) = 2*a(n), a(2n+1) = 1 + 2*a(A265354(n)).

A265352 Permutation of nonnegative integers: a(n) = A263273(A263272(n)).

Original entry on oeis.org

0, 1, 2, 3, 4, 7, 6, 19, 8, 9, 10, 5, 12, 13, 22, 21, 64, 23, 18, 55, 20, 57, 58, 25, 24, 73, 26, 27, 28, 11, 30, 31, 16, 15, 46, 17, 36, 37, 14, 39, 40, 67, 66, 199, 68, 63, 190, 65, 192, 193, 70, 69, 208, 71, 54, 163, 56, 165, 166, 61, 60, 181, 62, 171, 172, 59, 174, 175, 76, 75, 226, 77, 72, 217, 74, 219, 220, 79, 78, 235, 80, 81
Offset: 0

Views

Author

Antti Karttunen, Dec 07 2015

Keywords

Comments

Composition of A263273 with the permutation obtained from its even bisection.

Crossrefs

Programs

  • Python
    from sympy import factorint
    from sympy.ntheory.factor_ import digits
    from operator import mul
    def a030102(n): return 0 if n==0 else int(''.join(map(str, digits(n, 3)[1:][::-1])), 3)
    def a038502(n):
        f=factorint(n)
        return 1 if n==1 else reduce(mul, [1 if i==3 else i**f[i] for i in f])
    def a038500(n): return n/a038502(n)
    def a263273(n): return 0 if n==0 else a030102(a038502(n))*a038500(n)
    def a(n): return a263273(a263273(2*n)/2) # Indranil Ghosh, Jun 08 2017
  • Scheme
    (define (A265352 n) (A263273 (A263272 n)))
    

Formula

a(n) = A263273(A263272(n)).
As a composition of other related permutations:
a(n) = A265368(A264974(n)).
Other identities. For all n >= 0:
a(3*n) = 3*a(n).

A265353 Permutation of nonnegative integers: a(n) = A264985(A263273(n)).

Original entry on oeis.org

0, 1, 3, 2, 4, 10, 6, 9, 12, 5, 7, 19, 8, 13, 31, 24, 28, 37, 15, 11, 33, 18, 27, 30, 21, 36, 39, 14, 16, 46, 23, 25, 73, 69, 55, 64, 17, 22, 58, 26, 40, 94, 78, 85, 112, 51, 34, 100, 72, 82, 91, 75, 109, 118, 42, 32, 96, 20, 35, 105, 60, 99, 102, 45, 29, 87, 54, 81, 84, 57, 90, 93, 48, 38, 114, 63, 108, 111, 66, 117, 120, 41
Offset: 0

Views

Author

Antti Karttunen, Dec 07 2015

Keywords

Comments

Composition of A263273 with the permutation obtained from its odd bisection.

Crossrefs

Inverse: A265354.

Programs

  • Python
    from sympy import factorint
    from sympy.ntheory.factor_ import digits
    from operator import mul
    def a030102(n): return 0 if n==0 else int(''.join(map(str, digits(n, 3)[1:][::-1])), 3)
    def a038502(n):
        f=factorint(n)
        return 1 if n==1 else reduce(mul, [1 if i==3 else i**f[i] for i in f])
    def a038500(n): return n/a038502(n)
    def a263273(n): return 0 if n==0 else a030102(a038502(n))*a038500(n)
    def a264985(n): return (a263273(2*n + 1) - 1)/2
    def a(n): return a264985(a263273(n)) # Indranil Ghosh, May 22 2017
  • Scheme
    (define (A265353 n) (A264985 (A263273 n)))
    

Formula

a(n) = A264985(A263273(n)).

A265355 Permutation of nonnegative integers: a(n) = A263272(A264985(n)).

Original entry on oeis.org

0, 1, 3, 2, 4, 9, 6, 10, 12, 5, 11, 7, 8, 13, 27, 18, 28, 36, 15, 29, 21, 24, 37, 30, 33, 31, 39, 14, 32, 16, 17, 38, 19, 20, 34, 22, 23, 35, 25, 26, 40, 81, 54, 82, 108, 45, 83, 63, 72, 109, 90, 99, 85, 117, 42, 86, 48, 51, 110, 57, 60, 88, 66, 69, 89, 75, 78, 118, 84, 87, 91, 93, 96, 92, 102, 105, 112, 111, 114, 94, 120, 41
Offset: 0

Views

Author

Antti Karttunen, Dec 07 2015

Keywords

Comments

Composition of permutations obtained from the bisections of A263273.

Crossrefs

Programs

Formula

a(n) = A263272(A264985(n)).

A265356 Permutation of nonnegative integers: a(n) = A264985(A263272(n)).

Original entry on oeis.org

0, 1, 3, 2, 4, 9, 6, 11, 12, 5, 7, 10, 8, 13, 27, 18, 29, 30, 15, 32, 33, 20, 35, 36, 21, 38, 39, 14, 16, 19, 23, 25, 28, 24, 34, 37, 17, 22, 31, 26, 40, 81, 54, 83, 84, 45, 86, 87, 56, 89, 90, 57, 92, 93, 42, 95, 96, 59, 98, 99, 60, 101, 102, 47, 104, 105, 62, 107, 108, 63, 110, 111, 48, 113, 114, 65, 116, 117, 66, 119, 120, 41
Offset: 0

Views

Author

Antti Karttunen, Dec 07 2015

Keywords

Comments

Composition of permutations obtained from the bisections of A263273.

Crossrefs

Programs

Formula

a(n) = A264985(A263272(n)).

A266190 Self-inverse permutation of nonnegative integers: a(n) = A264985(A263273(A264985(n))).

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 9, 19, 12, 13, 14, 15, 16, 17, 24, 11, 69, 21, 25, 23, 18, 22, 26, 31, 28, 73, 30, 27, 46, 33, 55, 58, 37, 36, 64, 39, 40, 41, 42, 43, 44, 51, 32, 150, 48, 52, 50, 45, 49, 53, 78, 34, 213, 57, 35, 204, 60, 61, 231, 75, 38, 210, 66, 79, 68, 20, 70, 77, 72, 29, 207, 63, 76, 71, 54, 67, 80, 94, 85, 235
Offset: 0

Views

Author

Antti Karttunen, Jan 02 2016

Keywords

Comments

A263273 conjugated with the permutation obtained from its odd bisection.

Crossrefs

Cf. A265369, A265904, A266401, A266403 (other conjugates or similar derivations of A263273).
Cf. also A266189.

Programs

  • Mathematica
    f[n_] := Block[{g, h}, g[x_] := x/3^IntegerExponent[x, 3]; h[x_] := x/g@ x; If[n == 0, 0, FromDigits[Reverse@ IntegerDigits[#, 3], 3] &@ g[n] h[n]]]; s = Select[f /@ Range@ 5000, OddQ]; t = Table[(s[[n + 1]] - 1)/2, {n, 0, 1000}]; Table[t[[f[t[[n + 1]]] + 1]], {n, 0, 83}] (* Michael De Vlieger, Jan 04 2016, after Jean-François Alcover at A263273 *)
  • Scheme
    (define (A266190 n) (A264985 (A263273 (A264985 n))))

Formula

a(n) = A264985(A263273(A264985(n))).
As a composition of related permutations:
a(n) = A265353(A264985(n)).
a(n) = A264985(A265354(n)).

A265357 Permutation of nonnegative integers: a(n) = A264989(A263272(n)).

Original entry on oeis.org

0, 1, 2, 5, 4, 3, 6, 8, 11, 14, 16, 7, 17, 13, 9, 18, 32, 29, 15, 23, 20, 59, 26, 12, 56, 35, 38, 41, 43, 19, 50, 52, 10, 47, 25, 34, 44, 49, 22, 53, 40, 27, 54, 86, 83, 45, 95, 33, 167, 98, 30, 164, 89, 92, 42, 68, 24, 176, 71, 21, 60, 62, 65, 140, 77, 74, 179, 80, 36, 57, 113, 110, 137, 104, 101, 170, 107, 39, 173, 116, 119, 122
Offset: 0

Views

Author

Antti Karttunen, Dec 07 2015

Keywords

Comments

Composition of A263272 with the permutation obtained from its odd bisection.

Crossrefs

Programs

Formula

a(n) = A264989(A263272(n)).

A265358 Permutation of nonnegative integers: a(n) = A263272(A264989(n)).

Original entry on oeis.org

0, 1, 2, 5, 4, 3, 6, 11, 7, 14, 32, 8, 23, 13, 9, 18, 10, 12, 15, 29, 20, 59, 38, 19, 56, 34, 22, 41, 95, 17, 50, 113, 16, 47, 35, 25, 68, 104, 26, 77, 40, 27, 54, 28, 36, 45, 83, 33, 96, 37, 30, 87, 31, 39, 42, 86, 24, 69, 110, 21, 60, 101, 61, 176, 302, 62, 185, 119, 55, 164, 100, 58, 167, 299, 65, 194, 115, 64, 191, 103, 67, 122
Offset: 0

Views

Author

Antti Karttunen, Dec 07 2015

Keywords

Comments

Composition of A263272 with the permutation obtained from its odd bisection.

Crossrefs

Programs

Formula

a(n) = A263272(A264989(n)).

A265910 Zero-based column index to array A265345.

Original entry on oeis.org

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

Views

Author

Antti Karttunen, Dec 18 2015

Keywords

Crossrefs

One less than A265911.
Cf. A265345, A265352, A265354 (compare the scatter-plot).

Formula

a(2n+1) = A265354(n), a(2n) = a(A265352(n)).

A266189 Self-inverse permutation of nonnegative integers: a(n) = A263273(A264985(A263273(n))).

Original entry on oeis.org

0, 1, 3, 2, 4, 10, 6, 9, 12, 7, 5, 11, 8, 13, 37, 24, 28, 31, 21, 19, 57, 18, 27, 30, 15, 36, 39, 22, 16, 34, 23, 17, 35, 69, 29, 32, 25, 14, 38, 26, 40, 118, 78, 109, 112, 75, 46, 100, 72, 82, 91, 51, 85, 94, 66, 64, 192, 20, 73, 219, 60, 171, 138, 63, 55, 165, 54, 81, 84, 33, 90, 111, 48, 58, 174, 45, 108, 93, 42, 117, 120, 67, 49
Offset: 0

Views

Author

Antti Karttunen, Jan 02 2016

Keywords

Crossrefs

Programs

  • Mathematica
    f[n_] := Block[{g, h}, g[x_] := x/3^IntegerExponent[x, 3]; h[x_] := x/g@ x; If[n == 0, 0, FromDigits[Reverse@ IntegerDigits[#, 3], 3] &@ g[n] h[n]]]; s = Select[f /@ Range@ 5000, OddQ]; t = Table[(s[[n + 1]] - 1)/2, {n, 0, 1000}]; Table[f@ t[[f@ n + 1]], {n, 0, 82}] (* Michael De Vlieger, Jan 04 2016, after Jean-François Alcover at A263273 *)
  • Python
    from sympy import factorint
    from sympy.ntheory.factor_ import digits
    from operator import mul
    def a030102(n): return 0 if n==0 else int(''.join(map(str, digits(n, 3)[1:][::-1])), 3)
    def a038502(n):
        f=factorint(n)
        return 1 if n==1 else reduce(mul, [1 if i==3 else i**f[i] for i in f])
    def a038500(n): return n/a038502(n)
    def a263273(n): return 0 if n==0 else a030102(a038502(n))*a038500(n)
    def a264985(n): return (a263273(2*n + 1) - 1)/2
    def a(n): return a263273(a264985(a263273(n))) # Indranil Ghosh, May 22 2017
  • Scheme
    (define (A266189 n) (A263273 (A264985 (A263273 n))))
    

Formula

a(n) = A263273(A264985(A263273(n))).
As a composition of related permutations:
a(n) = A263273(A265353(n)).
a(n) = A265354(A263273(n)).
Showing 1-10 of 10 results.