Number of (n+1)X(n+1) -6..6 symmetric matrices with every 2X2 subblock having sum zero and three or four distinct values.
A211258
Number of (n+1)X(n+1) -6..6 symmetric matrices with every 2X2 subblock having sum zero and three or four distinct values.
Terms
- a(0) =64a(1) =322a(2) =1602a(3) =7994a(4) =39770a(5) =197618a(6) =980042a(7) =4851354a(8) =23971042a(9) =118229026a(10) =582129930a(11) =2861563514a(12) =14044992402a(13) =68835873986a(14) =336921033210
External references
- oeis: A211258