Principal diagonal of the convolution array A213841.

Terms

a(0) =1a(1) =24a(2) =101a(3) =264a(4) =545a(5) =976a(6) =1589a(7) =2416a(8) =3489a(9) =4840a(10) =6501a(11) =8504a(12) =10881a(13) =13664a(14) =16885a(15) =20576a(16) =24769a(17) =29496a(18) =34789a(19) =40680a(20) =47201a(21) =54384a(22) =62261a(23) =70864a(24) =80225a(25) =90376a(26) =101349a(27) =113176a(28) =125889a(29) =139520