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 31 results. Next

A349614 Dirichlet convolution of A064664 (the inverse permutation of EKG-permutation, A064413) with the Dirichlet inverse of A064413.

Original entry on oeis.org

1, 0, 1, -3, 7, -7, 2, 6, -8, -10, 5, 9, 14, 2, -41, -1, 17, 27, 15, -6, -38, -18, 13, 10, -32, -29, 18, 33, 18, 62, 29, -13, -31, -53, -107, 25, 48, -51, -86, 13, 30, 116, 58, 23, 88, -34, 37, -47, -30, 56, -113, 3, 45, -39, -137, -154, -73, -67, 41, 160, 84, -91, 174, 56, -154, 152, 91, 6, -113, 246, 58, -185, 56
Offset: 1

Views

Author

Antti Karttunen, Nov 23 2021

Keywords

Comments

Obviously, convolving this with A064413 gives its inverse permutation A064664.

Crossrefs

Cf. A064413, A064664, A349400, A349613 (Dirichlet inverse), A349615 (sum with it), A349617.
Cf. also pairs A349376, A349377 and A349397, A349398 for similar constructions.

Programs

  • PARI
    up_to = 32768;
    v064413 = readvec("b064413_upto65539_terms_only.txt"); \\ Data prepared with Chai Wah Wu's Dec 08 2014 Python-program given in A064413.
    A064413(n) = v064413[n];
    \\ Then its inverse A064664 is prepared:
    m064664 = Map();
    for(n=1,65539,mapput(m064664,A064413(n),n));
    A064664(n) = mapget(m064664,n);
    memoA349400 = Map();
    A349400(n) = if(1==n,1,my(v); if(mapisdefined(memoA349400,n,&v), v, v = -sumdiv(n,d,if(dA064413(n/d)*A349400(d),0)); mapput(memoA349400,n,v); (v)));
    A349614(n) = sumdiv(n,d,A064664(d)*A349400(n/d));

Formula

a(n) = Sum_{d|n} A064664(d) * A349400(n/d).

A304526 Möbius transform of A064664, the inverse of EKG-sequence.

Original entry on oeis.org

1, 1, 4, 1, 9, -2, 13, 5, 1, -2, 19, 2, 27, -2, -3, 9, 32, 7, 36, 8, -3, -2, 42, 4, 14, -2, 16, 12, 56, 15, 60, 14, -3, -2, 2, 15, 66, -2, -3, 17, 73, 23, 80, 21, 27, -2, 88, 20, 36, 23, -3, 19, 99, 20, 24, 18, -3, -2, 106, 18, 114, -2, 35, 33, 17, 41, 127, 32, -3, 33, 133, 24, 137, -2, 44, 34, 45, 44, 150, 23, 54, -2, 159, 27, 42, -2, -3, 33, 166, 25, 52
Offset: 1

Views

Author

Antti Karttunen, May 18 2018

Keywords

Crossrefs

Programs

Formula

a(n) = Sum_{d|n} A008683(n/d)*A064664(d).
a(n) = A064664(n) - A304527(n).
For all n >= 1, a(A000040(n)) = A064423(n).
For n >= 2, a(2*A000040(n)) = -2.
For n >= 3, a(3*A000040(n)) = -3.
a(n) = Sum_{d|n} A000010(n/d)*A349617(d). - Antti Karttunen, Jan 27 2024

A304527 Difference between A064664 (the inverse of EKG-sequence) and its Möbius-transform.

Original entry on oeis.org

0, 1, 1, 2, 1, 6, 1, 3, 5, 11, 1, 5, 1, 15, 14, 8, 1, 5, 1, 10, 18, 21, 1, 12, 10, 29, 6, 14, 1, 8, 1, 17, 24, 34, 23, 15, 1, 38, 32, 23, 1, 12, 1, 20, 12, 44, 1, 25, 14, 23, 37, 28, 1, 28, 29, 31, 41, 58, 1, 34, 1, 62, 16, 31, 37, 18, 1, 33, 47, 22, 1, 39, 1, 68, 25, 37, 33, 26, 1, 49, 22, 75, 1, 50, 42, 82, 61, 46, 1, 58, 41, 43, 65, 90, 46, 59, 1
Offset: 1

Views

Author

Antti Karttunen, May 18 2018

Keywords

Crossrefs

Programs

  • PARI
    A304527(n) = -sumdiv(n, d, (dA064664(d));

Formula

a(n) = A064664(n) - A304526(n).
a(n) = Sum_{d|n, dA304526(d).
a(n) = -Sum_{d|n, dA008683(n/d)*A064664(d).
For n >= 2, a(2*A000040(n))-1 = a(4*A000040(n)) = A064955(n). - Antti Karttunen, Dec 04 2022

A323411 Dirichlet inverse of A064664, the inverse permutation of EKG-sequence.

Original entry on oeis.org

1, -2, -5, 1, -10, 16, -14, -4, 19, 31, -20, -21, -28, 43, 89, 4, -33, -98, -37, -42, 125, 61, -43, 48, 76, 85, -87, -58, -57, -409, -61, -1, 179, 100, 255, 203, -67, 112, 251, 98, -74, -573, -81, -85, -559, 130, -89, -100, 146, -370, 296, -107, -100, 548, 347, 145, 332, 172, -107, 846, -115, 184, -783, 3, 506, -825, -128
Offset: 1

Views

Author

Antti Karttunen, Jan 13 2019

Keywords

Crossrefs

Programs

  • PARI
    up_to = 32768;
    v064413 = readvec("b064413_upto65539_terms_only.txt"); \\ From precomputed file.
    A064413(n) = v064413[n];
    \\ Then its inverse A064664 is prepared:
    m064664 = Map();
    for(n=1,65539,mapput(m064664,A064413(n),n));
    A064664(n) = mapget(m064664,n);
    DirInverse(v) = { my(u=vector(#v)); u[1] = (1/v[1]); for(n=2, #v, u[n] = -sumdiv(n, d, if(dA064664(n)));
    A323411(n) = v323411[n];

A323412 Sum of the inverse permutation of EKG-sequence, A064664, and its Dirichlet inverse, A323411.

Original entry on oeis.org

2, 0, 0, 4, 0, 20, 0, 4, 25, 40, 0, -14, 0, 56, 100, 21, 0, -86, 0, -24, 140, 80, 0, 64, 100, 112, -65, -32, 0, -386, 0, 30, 200, 132, 280, 233, 0, 148, 280, 138, 0, -538, 0, -44, -520, 172, 0, -55, 196, -324, 330, -60, 0, 596, 400, 194, 370, 228, 0, 898, 0, 244, -732, 67, 560, -766, 0, -70, 430, -1068, 0, -380, 0, 268, -1040, -78, 560
Offset: 1

Views

Author

Antti Karttunen, Jan 13 2019

Keywords

Crossrefs

Cf. also A304527, A323365.

Programs

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

Views

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).

A349617 Dirichlet convolution of A064664 (the inverse permutation of EKG-permutation) with A055615 (Dirichlet inverse of n).

Original entry on oeis.org

1, 0, 2, -1, 5, -6, 7, 2, -9, -11, 9, 2, 15, -15, -29, 1, 16, 18, 18, 5, -41, -21, 20, -4, -26, -29, 4, 7, 28, 64, 30, -3, -61, -34, -80, 9, 30, -38, -81, -6, 33, 92, 38, 14, 51, -44, 42, 10, -48, 53, -99, 6, 47, 4, -102, -17, -111, -58, 48, -4, 54, -62, 69, 2, -151, 146, 61, 18, -131, 157, 63, -3, 65, -68, 92, 18
Offset: 1

Views

Author

Antti Karttunen, Nov 23 2021

Keywords

Comments

Dirichlet convolution of this sequence with A000010 (Euler phi) is A304526 (Möbius transform of the inverse permutation of EKG-sequence).

Crossrefs

Cf. A055615, A064413, A064664, A349616 (Dirichlet inverse).
Cf. also A000010, A304526, A349614.

Programs

  • PARI
    A055615(n) = (n*moebius(n));
    v064413 = readvec("b064413_upto65539_terms_only.txt"); \\ Data prepared with Chai Wah Wu's Dec 08 2014 Python-program given in A064413.
    A064413(n) = v064413[n];
    \\ Then its inverse A064664 is prepared:
    m064664 = Map();
    for(n=1,65539,mapput(m064664,A064413(n),n));
    A064664(n) = mapget(m064664,n);
    A349617(n) = sumdiv(n,d,A064664(d)*A055615(n/d));

Formula

a(n) = Sum_{d|n} A064664(d) * A055615(n/d).

A255482 a(n) = A064664(n)-A255479(n).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Feb 28 2015

Keywords

Comments

Gives an idea of how similar A255582 is to A064413.

Crossrefs

Programs

A305294 Prime shift towards smaller primes, conjugated by the EKG-permutation: a(n) = A064664(A064989(A064413(n))).

Original entry on oeis.org

1, 1, 1, 2, 2, 3, 2, 1, 5, 5, 4, 3, 10, 10, 9, 2, 1, 5, 14, 14, 13, 8, 4, 6, 11, 10, 20, 20, 19, 3, 1, 28, 28, 27, 9, 33, 33, 32, 7, 5, 14, 37, 37, 36, 2, 6, 20, 8, 10, 24, 18, 4, 15, 21, 11, 43, 43, 42, 13, 57, 57, 56, 3, 1, 28, 61, 61, 60, 12, 19, 33, 5, 67, 67, 66, 17, 9, 25, 14, 74, 74, 73, 7, 29, 34, 6, 37, 81, 81, 80, 2
Offset: 1

Views

Author

Antti Karttunen, May 31 2018

Keywords

Crossrefs

Formula

a(n) = A064664(A064989(A064413(n))).
For all n >= 1, a(A305293(n)) = n.
For all n >= 2, a(A064423(n)) = a(A064955(n)) = A064955(n-1).
For all n >= 3, a(1+A064955(n)) = A064423(n-1).

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 1-10 of 31 results. Next