S(n,1) + S(n-1,2) + S(n-2,3) + ... + S(n+1-k,k), where k = floor((n+1)/2) and S(i,j) are Stirling numbers of the second kind.

A024427

S(n,1) + S(n-1,2) + S(n-2,3) + ... + S(n+1-k,k), where k = floor((n+1)/2) and S(i,j) are Stirling numbers of the second kind.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =4a(4) =9a(5) =22a(6) =58a(7) =164a(8) =495a(9) =1587a(10) =5379a(11) =19195a(12) =71872a(13) =281571a(14) =1151338a(15) =4902687a(16) =21696505a(17) =99598840a(18) =473466698a(19) =2327173489a(20) =11810472444a(21) =61808852380a(22) =333170844940

External references