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A132686
a(n) = binomial(2^n + 2*n + 1, n).
13
1, 5, 36, 455, 12650, 962598, 237093780, 209004408899, 689960224294614, 8639439963148103450, 409865407260324119340236, 73328394245057556170201283726, 49287010273876375495535472789937580
OFFSET
0,2
LINKS
FORMULA
a(n) = [x^n] 1/(1-x)^(2^n + n + 2).
MATHEMATICA
Table[Binomial[2^n +2*n +1, n], {n, 0, 20}] (* G. C. Greubel, Mar 13 2021 *)
PROG
(PARI) a(n)=binomial(2^n+2*n+1, n)
(Sage) [binomial(2^n +2*n +1, n) for n in (0..20)] # G. C. Greubel, Mar 13 2021
(Magma) [Binomial(2^n +2*n +1, n): n in [0..20]]; // G. C. Greubel, Mar 13 2021
CROSSREFS
Sequences of the form binomial(2^n +p*n +q, n): A136556 (0,-1), A014070 (0,0), A136505 (0,1), A136506 (0,2), A060690 (1,-1), A132683 (1,0), A132684 (1,1), A132685 (2,0), this sequence (2,1), A132687 (3,-1), A132688 (3,0), A132689 (3,1).
Cf. A136555.
Sequence in context: A365356 A194958 A241346 * A322180 A351019 A252782
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Aug 26 2007
STATUS
approved