a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (composite numbers), t = (odd natural numbers).

A025104

a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (composite numbers), t = (odd natural numbers).

Terms

    a(0) =12a(1) =20a(2) =58a(3) =78a(4) =154a(5) =190a(6) =307a(7) =361a(8) =525a(9) =599a(10) =829a(11) =927a(12) =1235a(13) =1361a(14) =1742a(15) =1898a(16) =2358a(17) =2546a(18) =3112a(19) =3336a(20) =4020a(21) =4284a(22) =5073a(23) =5379a(24) =6279a(25) =6629a(26) =7675a(27) =8073a(28) =9246a(29) =9694

External references