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Number of partitions p of n such that each part of p is prime and each part of the conjugate partition of p is also prime.
0

%I #10 Jan 09 2013 15:58:56

%S 0,0,0,1,0,2,0,1,1,2,0,2,2,2,2,3,3,0,4,2,5,2,4,3,8,2,6,4,11,0,10,4,14,

%T 2,14,4,21,2,20,5,25,0,28,6,30,2,38,5,46,0,44,4,54,0,56,6,67,2,72,4,

%U 93,2,74,7,113,0,100,8,131,0,128

%N Number of partitions p of n such that each part of p is prime and each part of the conjugate partition of p is also prime.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PrimePartition.html">Prime Partition.</a>

%e For n=17, there are three valid partitions: (7,7,3), its conjugate partition (3,3,3,2,2,2,2), and the self-conjugate partition (5,5,3,2,2).

%e Thus a(17)=3.

%t ConjugatePartition[l_List] :=

%t Module[{i, r = Reverse[l], n = Length[l]},

%t Table[n + 1 - Position[r, _?(# >= i &), Infinity, 1][[1, 1]], {i,

%t l[[1]]}]];f[n_] := Select[Select[IntegerPartitions[n], And @@ (PrimeQ[#]) &],

%t And @@ (PrimeQ[ConjugatePartition[#]]) &];a[n_] := Length[f[n]];Table[a[n],{n,1,40}]

%Y Cf. A000040, A000041, A000607

%K nonn

%O 1,6

%A _Ben Branman_, Jan 09 2013