Search: id:A120732 Results 1-1 of 1 results found. %I A120732 %S A120732 1,1,3,15,107,991,11267,151721,2360375,41650861,821881709,17932031225, %T A120732 428630422697,11138928977049,312680873171465,9428701154866535, %U A120732 303957777464447449,10431949496859168189,379755239311735494421 %N A120732 Number of square matrices with nonnegative integer entries and without zero rows or columns such that sum of all entries is equal to n. %F A120732 a(n) = (1/n!)*Sum_{k=0..n} (-1)^(n-k)*Stirling1(n,k)*A048144(k). G.f.: Sum_{n>=0} Sum_{j=0..n} (-1)^(n-j)*binomial(n,j)*((1-x)^(-j)-1)^n. %Y A120732 Cf. A104602. %Y A120732 Sequence in context: A120016 A074519 A105618 this_sequence A090351 A136221 A153305 %Y A120732 Adjacent sequences: A120729 A120730 A120731 this_sequence A120733 A120734 A120735 %K A120732 nonn %O A120732 0,3 %A A120732 Vladeta Jovovic (vladeta(AT)eunet.rs), Aug 18 2006 Search completed in 0.001 seconds