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.

A334201 a(n) = A056239(n) - A061395(n).

Original entry on oeis.org

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

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Author

Antti Karttunen, May 11 2020

Keywords

Comments

a(n) is the sum of all other parts of the partition having Heinz number n except one instance of the largest part.

Crossrefs

Sum of A339895 and A339896.
Differs from A323077 for the first time at n=169, where a(169) = 6, while A323077(169) = 5.
Cf. also A334107.

Programs

  • Mathematica
    Array[Total[# /. {p_, c_} /; p > 0 :> PrimePi[p] c] - PrimePi@ #[[-1, 1]] &@ FactorInteger[#] &, 105] (* Michael De Vlieger, May 14 2020 *)
  • PARI
    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)};
    A334201(n) = if(1==n,0,(bigomega(n)-1)+A334201(A064989(n)));

Formula

a(n) = A056239(n) - A061395(n) = A056239(A052126(n)).
a(n) = A318995(A122111(n)).
a(n) = a(A064989(n)) + A001222(n) - 1.
a(n) = A339895(n) + A339896(n). - Antti Karttunen, Dec 31 2020