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%I #12 Nov 28 2022 03:39:50
%S 1,1,1,0,1,2,1,2,2,3,5,2,4,4,5,5,8,4,8,6,8,7,11,6,12,9,13,9,14,10,16,
%T 12,14,13,19,13,22,14,17,17,22,16,24,18,22,19,25,18,28,21,28,21,28,22,
%U 32,25,30,25,33,26,38,28,31,29,38,29,42,30,34,33,42
%N Number of compositions (ordered partitions) of n into at most 2 nonprime parts.
%H Antti Karttunen, <a href="/A347788/b347788.txt">Table of n, a(n) for n = 0..10000</a>
%t Table[Length@Flatten[Permutations/@IntegerPartitions[n,2,Select[Range@n,!PrimeQ@#&]],1],{n,0,70}] (* _Giorgos Kalogeropoulos_, Sep 13 2021 *)
%o (PARI) A347788(n) = if(n<2,1,!isprime(n)+sum(k=1,n-1,!(isprime(k)+isprime(n-k)))); \\ _Antti Karttunen_, Nov 25 2022
%Y Cf. A005171, A018252, A052284, A076608, A347796, A347797, A347798, A347799, A358638.
%K nonn
%O 0,6
%A _Ilya Gutkovskiy_, Sep 13 2021