Convolution of A007947 with itself.

Terms

a(0) =1a(1) =4a(2) =10a(3) =16a(4) =27a(5) =44a(6) =72a(7) =88a(8) =105a(9) =132a(10) =194a(11) =232a(12) =259a(13) =324a(14) =464a(15) =544a(16) =593a(17) =636a(18) =862a(19) =904a(20) =999a(21) =1092a(22) =1500a(23) =1576a(24) =1689a(25) =1852a(26) =2210a(27) =2192a(28) =2307a(29) =2460