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A232721 Numbers not representable as the sum of two coprime nonprime numbers. 0
1, 3, 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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Numbers n such that A185279(n) = 0. 1 and 3 together with A141096.

LINKS

Table of n, a(n) for n=1..28.

MATHEMATICA

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

CROSSREFS

Cf. A062303, A018252, A141095, A141098.

Sequence in context: A203444 A008864 A214583 * A227956 A225531 A129295

Adjacent sequences:  A232718 A232719 A232720 * A232722 A232723 A232724

KEYWORD

nonn,full,fini

AUTHOR

Irina Gerasimova, Nov 28 2013

STATUS

approved

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Last modified September 26 15:27 EDT 2017. Contains 292531 sequences.