Self-convolution of A107592.

Terms

a(0) =1a(1) =2a(2) =7a(3) =32a(4) =169a(5) =976a(6) =5989a(7) =38398a(8) =254509a(9) =1731596a(10) =12032874a(11) =85092944a(12) =610714311a(13) =4439136084a(14) =32626373027a(15) =242153129074