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A146977
a(n) = Sum_{k=1..prime(n)} binomial(2k,k).
3
8, 28, 350, 4706, 956384, 14061140, 3143981870, 47564380970, 11061198475550, 40328534467494098, 624021469287616610, 2338958497948612884092, 568740383597968804344752, 8885203954833615367662872, 2175457720411301277807088352, 8390179243143767727343229863076
OFFSET
1,1
LINKS
MAPLE
seq( add(binomial(2*k, k), k=1..ithprime(n)), n=1..15); # G. C. Greubel, Jan 09 2020
MATHEMATICA
Table[Sum[Binomial[2k, k], {k, Prime[n]}], {n, 15}] (* Harvey P. Dale, Dec 31 2012 *)
PROG
(PARI) vector(15, n, sum(k=1, prime(n), binomial(2*k, k)) ) \\ G. C. Greubel, Jan 09 2020
(Magma) [ &+[Binomial(2*k, k): k in [1..NthPrime(n)]]: n in [1..15]]; // G. C. Greubel, Jan 09 2020
(Sage) [sum(binomial(2*k, k) for k in (1..nth_prime(n))) for n in (1..15)] # G. C. Greubel, Jan 09 2020
CROSSREFS
A subsequence of A066796.
Sequence in context: A374280 A244613 A228281 * A374138 A068623 A361585
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Apr 25 2009
STATUS
approved