A062311 - OEIS

%I #11 Mar 25 2023 23:35:58

%S 0,0,0,1,3,12,39,184,951,5531,38713,346207,3130812,34444964,382437428,

%T 4637235145

%N Number of ways writing n! as a sum of two primes.

%C Number of unordered pairs of primes (p,q) such that n! = p + q.

%F In other words, a(n) = A061358(n!) = number of prime+prime partitions of n!.

%e n = 4: 4! = 24 = 5+19 = 7+17 = 11+13 so a(4) = 3.

%Y Cf. A061358, A000142. See A140088 for a variant.

%K nonn,more

%O 0,5

%A _Labos Elemer_, Jul 05 2001

%E a(9)-a(12) from _Hans Havermann_, Apr 29 2008

%E a(13) from _Graeme McRae_, May 02 2008

%E a(14)-a(15) from _Hans Havermann_, Dec 21 2008