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A341483 Number of ways to write n as an ordered sum of 6 nonprime numbers.

%I A341483 #7 Feb 13 2021 14:17:54
%S A341483 1,0,0,6,0,6,15,6,36,26,45,96,75,156,201,242,375,456,586,816,987,1256,
%T A341483 1656,1962,2512,3102,3717,4616,5577,6612,8067,9516,11283,13372,15678,
%U A341483 18378,21412,24966,28719,33388,38244,43872,50248,57288,64914,74074,83328,94248
%N A341483 Number of ways to write n as an ordered sum of 6 nonprime numbers.
%p A341483 b:= proc(n, t) option remember;
%p A341483       `if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add(
%p A341483       `if`(isprime(j), 0, b(n-j, t-1)), j=1..n)))
%p A341483     end:
%p A341483 a:= n-> b(n, 6):
%p A341483 seq(a(n), n=6..53);  # _Alois P. Heinz_, Feb 13 2021
%t A341483 nmax = 53; CoefficientList[Series[Sum[Boole[!PrimeQ[k]] x^k, {k, 1, nmax}]^6, {x, 0, nmax}], x] // Drop[#, 6] &
%Y A341483 Cf. A005171, A018252, A052284, A076608, A340962, A341453, A341465, A341480, A341481, A341482, A341484, A341485, A341486.
%K A341483 nonn
%O A341483 6,4
%A A341483 _Ilya Gutkovskiy_, Feb 13 2021