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A101434 Composite numbers which are the product of non-twin primes. 0
4, 8, 16, 32, 46, 64, 74, 92, 94, 106, 128, 134, 148, 158, 166, 178, 184, 188, 194, 212, 226, 254, 256, 262, 268, 296, 314, 316, 326, 332, 334, 346, 356, 368, 376, 388, 422, 424, 446, 452, 466, 502, 508, 512, 514, 524, 526, 529, 536, 554, 586, 592, 614, 628, 632 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..55.

EXAMPLE

74 = 2*37, 529 = 23*23.

MATHEMATICA

nn = 150; p = Prime[Range[nn]]; t = {2}; Do[If[p[[n + 1]] - p[[n]] != 2 && p[[n]] - p[[n - 1]] != 2, AppendTo[t, p[[n]]]], {n, 2, nn - 1}]; Select[Range[2, t[[-1]]], ! PrimeQ[#] && Complement[Transpose[FactorInteger[#]][[1]], t] == {} &] (* T. D. Noe, May 21 2013 *)

CROSSREFS

Cf. A100819.

Sequence in context: A088259 A123857 A217313 * A293780 A048168 A175341

Adjacent sequences:  A101431 A101432 A101433 * A101435 A101436 A101437

KEYWORD

easy,nonn

AUTHOR

Walter Carlini, Jan 18 2005

EXTENSIONS

Corrected and extended by Arkadiusz Wesolowski, May 21 2013

STATUS

approved

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Last modified April 19 06:30 EDT 2019. Contains 322237 sequences. (Running on oeis4.)