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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.

User: Oscar Granfeldt

Oscar Granfeldt's wiki page.

Oscar Granfeldt has authored 1 sequences.

A348675 a(n) = Sum_{k=0..n-1} Omega(n^2-k^2).

Original entry on oeis.org

0, 3, 6, 10, 14, 18, 21, 27, 31, 35, 39, 44, 48, 54, 58, 64, 68, 74, 77, 83, 87, 91, 96, 102, 107, 112, 117, 123, 127, 132, 135, 144, 149, 153, 158, 164, 167, 173, 178, 184, 190, 195, 199, 205, 210, 215, 219, 227, 231, 238, 242, 247, 252, 258, 262, 269, 273, 278
Offset: 1

Author

Oscar Granfeldt, Oct 29 2021

Keywords

Examples

			For n = 3, row 3 of A094728 is 9, 8, 5, and a(3) = Omega(9)+Omega(8)+Omega(5) = 2+3+1 = 6.
		

Crossrefs

Programs

  • Maple
    a := n -> add(NumberTheory:-NumberOfPrimeFactors(n*n - k*k), k = 0..n-1):
    seq(a(n), n = 1..58);
  • Mathematica
    a[n_] := Sum[PrimeOmega[n^2 - k^2], {k, 0, n - 1}]; Array[a, 60] (* Amiram Eldar, Oct 30 2021 *)
  • PARI
    a(n) = sum(k=0, n-1, bigomega(n^2-k^2)); \\ Michel Marcus, Oct 30 2021

Formula

a(n) = Sum_{k=0..n-1} A001222(A094728(n,k)).