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%I #13 Sep 07 2023 16:09:15
%S 4,6,8,10,12,14,16,18,20,28,30,32,40,42,44,58,60,62,70,72,74,100,102,
%T 104,106,108,110,136,138,140,148,150,152,178,180,182,190,192,194,196,
%U 198,200,226,228,230,238,240,242,268,270,272,280,282,284
%N Triple composites.
%C Numbers that are composites and nearest-neighbors of twin primes.
%H Harvey P. Dale, <a href="/A134928/b134928.txt">Table of n, a(n) for n = 1..1000</a>
%H Omar E. Pol, <a href="http://www.polprimos.com">Determinacion geometrica de los numeros primos y compuesto</a>.
%e 28, 30 and 32 are triple composites because 29 and 31 are twin primes and 28, 30 and 32 are composites and nearest-neighbors of 29 and 31.
%t #[[1]]+{-1,1,3}&/@Select[Partition[Prime[Range[3,100]],2,1],#[[2]]-#[[1]]==2&]//Flatten (* _Harvey P. Dale_, Jun 09 2023 *)
%t Flatten[{#[[1]],#[[1]]+2,#[[2]]}&/@SequencePosition[Table[Which[CompositeQ[ n],1,PrimeQ[ n],2,True,0],{n,300}],{1,2,1,2,1}]] (* _Harvey P. Dale_, Sep 07 2023 *)
%Y Cf. Twin primes = A001097, Composite numbers = A002808.
%K easy,nonn
%O 1,1
%A _Omar E. Pol_, Nov 16 2007