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A109934 Composite numbers which are not the sum of two distinct primes. 4
4, 6, 27, 35, 51, 57, 65, 77, 87, 93, 95, 117, 119, 121, 123, 125, 135, 143, 145, 147, 155, 161, 171, 177, 185, 187, 189, 203, 205, 207, 209, 215, 217, 219, 221, 237, 245, 247, 249, 255, 261, 267, 275, 287, 289, 291, 297, 299, 301, 303, 305, 321, 323, 325, 327 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Perhaps there are no even terms > 6.

LINKS

T. D. Noe, Table of n, a(n) for n = 1..10000

MATHEMATICA

f[n_] := (p = 0; pn = PrimePi[n];

Do[ If[n == Prime[i] + Prime[k], p = p + 1; If[p > 2, Break[]]], {i, 1, pn},

{k, i+1, pn}]; p );

Select[Range[2, 400], ! PrimeQ[#] && f[#] == 0 & ] (* Jean-Fran├žois Alcover, Mar 07 2011 *)

CROSSREFS

Cf. A025583.

Sequence in context: A074120 A054265 A105409 * A068321 A012896 A013078

Adjacent sequences:  A109931 A109932 A109933 * A109935 A109936 A109937

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Jul 19 2005

STATUS

approved

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Last modified January 22 11:34 EST 2019. Contains 319363 sequences. (Running on oeis4.)