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A101434 Composite numbers which are the product of non-twin primes. 0

%I #10 Feb 18 2015 11:02:50

%S 4,8,16,32,46,64,74,92,94,106,128,134,148,158,166,178,184,188,194,212,

%T 226,254,256,262,268,296,314,316,326,332,334,346,356,368,376,388,422,

%U 424,446,452,466,502,508,512,514,524,526,529,536,554,586,592,614,628,632

%N Composite numbers which are the product of non-twin primes.

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

%t 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 *)

%Y Cf. A100819.

%K easy,nonn

%O 1,1

%A _Walter Carlini_, Jan 18 2005

%E Corrected and extended by _Arkadiusz Wesolowski_, May 21 2013

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Last modified April 18 22:18 EDT 2024. Contains 371782 sequences. (Running on oeis4.)