A084847 a(n) = 2*3^n+2^(2n-1)*(n-2).

1, 4, 18, 86, 418, 2022, 9650, 45334, 209730, 956870, 4312402, 19228662, 84948962, 372287398, 1620178674, 7008019670, 30150864514, 129107299206, 550530654866, 2338786731958, 9902578218786, 41802362561894, 175984622563378

Offset: 0

Author

Paul Barry, Jun 09 2003

Keywords

• easy
• nonn

Comments

Binomial transform of A084643. Third binomial transform of abs(A060747).

Links

• Index entries for linear recurrences with constant coefficients, signature (11,-40,48).

Crossrefs

Cf. A060747, A084643.

Formula

G.f.: (1-7x+14x^2)/((1-3x)(1-4x)^2).