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.

A300723 Möbius-transform of A005187(A053645(n)).

Original entry on oeis.org

0, 0, 1, 0, 1, 2, 4, 0, 0, 2, 4, 4, 8, 6, 9, 0, 1, 0, 4, 4, 3, 6, 11, 8, 15, 10, 18, 12, 23, 10, 26, 0, -4, 2, -1, 0, 8, 6, 2, 8, 16, 2, 19, 12, 12, 14, 26, 16, 28, 16, 33, 20, 39, 20, 37, 24, 42, 26, 50, 20, 54, 30, 49, 0, -8, -6, 4, 4, -4, -2, 11, 0, 16, 10, -7, 12, 15, 2, 26, 16, 13, 18, 35, 4, 37, 22, 18, 24, 47, 12
Offset: 1

Views

Author

Antti Karttunen, Mar 12 2018

Keywords

Crossrefs

Programs

  • Mathematica
    With[{s = Array[2 # - DigitCount[2 #, 2, 1] &[# - 2^Floor@ Log2@ #] &, 90]}, Table[DivisorSum[n, MoebiusMu[n/#] s[[#]] &], {n, Length@ s}]] (* Michael De Vlieger, Mar 13 2018 *)
  • PARI
    A005187(n) = { my(s=n); while(n>>=1, s+=n); s; };
    A053644(n) = { my(k=1); while(k<=n, k<<=1); (k>>1); }; \\ From A053644
    A053645(n) = (n-A053644(n));
    A300723(n) = sumdiv(n,d,moebius(n/d)*A005187(A053645(d)));

Formula

a(n) = Sum_{d|n} A008683(n/d)*A005187(A053645(d)).
a(1) = 0; for n > 1, a(n) = A297111(n) - 2*A300724(n).