Number of (n+1) X (n+1) -11..11 symmetric matrices with every 2 X 2 subblock having sum zero and two distinct values.
A211710
Number of (n+1) X (n+1) -11..11 symmetric matrices with every 2 X 2 subblock having sum zero and two distinct values.
Terms
- a(0) =34a(1) =46a(2) =64a(3) =94a(4) =142a(5) =220a(6) =346a(7) =550a(8) =880a(9) =1414a(10) =2278a(11) =3676a(12) =5938a(13) =9598a(14) =15520a(15) =25102a(16) =40606a(17) =65692a(18) =106282a(19) =171958a(20) =278224a(21) =450166a(22) =728374a(23) =1178524a(24) =1906882a(25) =3085390a(26) =4992256a(27) =8077630a(28) =13069870a(29) =21147484
External references
- oeis: A211710