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.

A141098 Even numbers not representable as the sum of two coprime composite numbers.

Original entry on oeis.org

2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 36, 38, 40, 42, 48, 50, 54, 56, 60, 66, 70, 72, 78, 80, 84, 90, 96, 108, 110, 120, 126, 132, 138, 140, 150, 180, 210
Offset: 1

Views

Author

T. D. Noe, Jun 02 2008

Keywords

Comments

210 is the last term.

Crossrefs

This sequence is a superset of A141096. See A141097.

Programs

  • Mathematica
    t = Table[Length[Select[Range[2, n/2], ! PrimeQ[#] && ! PrimeQ[n - #] && GCD[#, n - #] == 1 &]], {n, 2, 2000, 2}]; Flatten[2*Position[t, 0]] (* T. D. Noe, Dec 05 2013 *)