Number of ways to place a non-attacking white and black pawn on n X n chessboard.

Terms

a(0) =0a(1) =0a(2) =6a(3) =50a(4) =194a(5) =522a(6) =1142a(7) =2186a(8) =3810a(9) =6194a(10) =9542a(11) =14082a(12) =20066a(13) =27770a(14) =37494a(15) =49562a(16) =64322a(17) =82146a(18) =103430a(19) =128594a(20) =158082a(21) =192362a(22) =231926a(23) =277290a(24) =328994a(25) =387602a(26) =453702a(27) =527906a(28) =610850a(29) =703194