A051139 a(n) = A000994(n+2) - A000995(n+2).

1, 0, 0, 1, 3, 7, 19, 64, 236, 893, 3489, 14347, 62429, 285580, 1362372, 6749337, 34683211, 184774851, 1019351071, 5813020060, 34206071992, 207391313189, 1294092695729, 8302365433863, 54713262186745, 370027343460584, 2565874205681368

Offset

0,5

Links

Reinhard Zumkeller, Table of n, a(n) for n = 0..100

Formula

For recurrence see A000994 and A000995.

Example

a(7) = 359 - 295 = 64.

Mathematica

a4[_?Negative] = 0; a4[n_] := a4[n] = 1 + Sum[ Binomial[n, k]*a4[k-2], {k, 2, n}]; a5[_?Negative] = 0; a5[n_] := a5[n] = n + Sum[ Binomial[n, k]*a5[k-2], {k, 2, n}]; a[n_] := a4[n] - a5[n]; Table[a[n], {n, 0, 26}] (* Jean-François Alcover, Oct 11 2013 *)

Prog

(Haskell)
a051139 n = a000994 (n + 2) - a000995 (n + 2)
-- Reinhard Zumkeller, Jun 02 2013

Crossrefs

Cf. A000994, A000995.

Sequence in context: A364626 A210985 A160128 * A049423 A121825 A066237

Adjacent sequences: A051136 A051137 A051138 * A051140 A051141 A051142

Keyword

nonn,easy,eigen,nice

Author

N. J. A. Sloane

Status

approved