A141096 Even numbers not representable as the sum of two coprime nonprime numbers.

4, 6, 8, 12, 14, 18, 20, 24, 30, 32, 38, 42, 48, 54, 60, 72, 80, 84, 90, 108, 110, 132, 138, 140, 150, 180

Offset

1,1

Comments

Numbers k such that A141095(k/2) = 0.

180 is the last term.

This sequence is a subsequence of A141098.

Links

Table of n, a(n) for n=1..26.

Mathematica

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

Crossrefs

Cf. A141095, A141098.

Sequence in context: A275671 A370745 A055670 * A089257 A113451 A270191

Adjacent sequences: A141093 A141094 A141095 * A141097 A141098 A141099

Keyword

nonn,fini,full

Author

T. D. Noe, Jun 02 2008

Status

approved