Sum of the k-th pi-based arithmetic derivative of n-k for k=0..n.

Terms

a(0) =0a(1) =1a(2) =2a(3) =4a(4) =6a(5) =10a(6) =13a(7) =20a(8) =21a(9) =33a(10) =54a(11) =86a(12) =146a(13) =339a(14) =788a(15) =2947a(16) =14870a(17) =94801a(18) =706961a(19) =5566784a(20) =43958933a(21) =317950465a(22) =2406052444a(23) =19645433193a(24) =146175038733