Number of magic labelings with magic sum n of 2nd graph shown in link.

Terms

a(0) =1a(1) =8a(2) =37a(3) =121a(4) =318a(5) =717a(6) =1446a(7) =2678a(8) =4639a(9) =7614a(10) =11955a(11) =18087a(12) =26516a(13) =37835a(14) =52732a(15) =71996a(16) =96525a(17) =127332a(18) =165553a(19) =212453a(20) =269434a(21) =338041a(22) =419970a(23) =517074a(24) =631371a(25) =765050a(26) =920479a(27) =1100211a(28) =1306992a(29) =1543767