A026975 a(n) = Sum{(k+1)*T(n,k)}, 0<=k<=n, T given by A026648.

1, 3, 10, 25, 66, 154, 392, 882, 2180, 4796, 11640, 25220, 60424, 129480, 307264, 652936, 1538064, 3247024, 7604000, 15968400, 37217312, 77818016, 180652416, 376359200, 870795328, 1808574912, 4172640640, 8643327040