A278858 a(n) = permanent M_n where M_n is the n X n matrix m(i,j) = abs(i^2-j^2).

1, 0, 9, 240, 36864, 7741440, 3363235524, 2203143038208, 2248347011420160, 3260265586467690240, 6578570637254005920000, 17755898734939822501524480, 62673017366111480630785474560, 282641923592380319367599892725760, 1599753679036773033206787507696238848

Offset: 0

Author

Vaclav Kotesovec, Nov 29 2016

Keywords

• nonn

Links

• Vaclav Kotesovec, Table of n, a(n) for n = 0..36

Crossrefs

Cf. A085750, A085807, A204249, A278845, A278847, A278857.

Programs

Mathematica

Flatten[{1, Table[Permanent[Table[Abs[i^2-j^2], {i, 1, n}, {j, 1, n}]], {n, 1, 15}]}]

PARI

{a(n) = matpermanent(matrix(n, n, i, j, abs(i^2-j^2)))}
for(n=0, 20, print1(a(n), ", ")) \\ Vaclav Kotesovec, Aug 12 2021