Number of non-isomorphic 5 X 5 nonnegative integer symmetric matrices with all row and column sums equal to n up to permutations of rows and columns.

A333887

Number of non-isomorphic 5 X 5 nonnegative integer symmetric matrices with all row and column sums equal to n up to permutations of rows and columns.

Terms

    a(0) =1a(1) =1a(2) =7a(3) =29a(4) =142a(5) =556a(6) =1919a(7) =5793a(8) =15758a(9) =39131a(10) =90185a(11) =194905a(12) =398773a(13) =777708a(14) =1454721a(15) =2622421a(16) =4575020a(17) =7750397a(18) =12787648a(19) =20600441a(20) =32473894a(21) =50185556a(22) =76161130a(23) =113665307a(24) =167041499a(25) =242001146a(26) =345981348a(27) =488570133a(28) =682023069a(29) =941871068

External references