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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A305293 Prime shift towards larger primes, conjugated by the EKG-permutation: a(n) = A064664(A003961(A064413(n))).

Original entry on oeis.org

1, 5, 6, 11, 10, 24, 39, 22, 15, 14, 25, 69, 21, 20, 53, 130, 76, 51, 29, 28, 54, 112, 97, 50, 78, 96, 34, 33, 84, 209, 232, 38, 37, 85, 153, 44, 43, 111, 156, 179, 109, 58, 57, 142, 383, 140, 148, 352, 281, 124, 249, 299, 93, 118, 218, 62, 61, 143, 172, 68, 67, 173, 641, 696, 162, 75, 74, 210, 227, 238, 191, 535, 82, 81
Offset: 1

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Author

Antti Karttunen, May 31 2018

Keywords

Comments

Permutation of A064957.

Crossrefs

Cf. A305294 (a left inverse).

Formula

a(n) = A064664(A003961(A064413(n))).
Other identities. For all n >= 1:
A305294(a(n)) = n.
a(A064955(n)) = A064955(1+n).
For all n >= 2, a(A064423(n)) = 1+A064955(1+n).

A318664 Numerators of the sequence whose Dirichlet convolution with itself yields A064664, the inverse permutation of EKG-sequence.

Original entry on oeis.org

1, 1, 5, 1, 5, -1, 7, 3, -1, -1, 10, 3, 14, -1, -7, 5, 33, 59, 37, 9, -10, -1, 43, -1, -1, -1, 181, 13, 57, 89, 61, 15, -29, -1, -45, 31, 67, -1, -41, 1, 37, 129, 81, 11, 301, -1, 89, 21, 1, 26, -97, 10, 50, -93, -47, -5, -109, -1, 107, -33, 115, -1, 411, 15, -43, 201, 64, 33, -127, 56, 67, 181, 69, -1, 283, 35, -31, 255, 151, 7
Offset: 1

Views

Author

Antti Karttunen, Sep 01 2018

Keywords

Crossrefs

Cf. A064664, A304526, A304527, A305293, A305294, A318665 (denominators).
Cf. also A317929, A317930.

Programs

  • PARI
    v064413 = readvec("b064413_upto65539_terms_only.txt"); \\ From b-file of A064413 prepared beforehand.
    A064413(n) = v064413[n];
    m064664 = Map();
    for(n=1,65539,mapput(m064664,A064413(n),n));
    A064664(n) = mapget(m064664,n);
    up_to = (2^14);
    DirSqrt(v) = {my(n=#v, u=vector(n)); u[1]=1; for(n=2, n, u[n]=(v[n]/v[1] - sumdiv(n, d, if(d>1&&dA317937.
    v318664_65 = DirSqrt(vector(up_to, n, A064664(n)));
    A318664(n) = numerator(v318664_65[n]);
    A318665(n) = denominator(v318664_65[n]);

Formula

a(n) = numerator of f(n), where f(1) = 1, f(n) = (1/2) * (A064664(n) - Sum_{d|n, d>1, d 1.
For n >= 2, a(2*A000040(n)) = -1.
Showing 1-2 of 2 results.