Convolution of 5^n and floor(n/2).

Terms

a(0) =0a(1) =0a(2) =1a(3) =6a(4) =32a(5) =162a(6) =813a(7) =4068a(8) =20344a(9) =101724a(10) =508625a(11) =2543130a(12) =12715656a(13) =63578286a(14) =317891437a(15) =1589457192a(16) =7947285968a(17) =39736429848a(18) =198682149249a(19) =993410746254