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A152670
Even Catalan numbers.
3
2, 14, 42, 132, 1430, 4862, 16796, 58786, 208012, 742900, 2674440, 35357670, 129644790, 477638700, 1767263190, 6564120420, 24466267020, 91482563640, 343059613650, 1289904147324, 4861946401452, 18367353072152, 69533550916004
OFFSET
1,1
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..541 [duplicated terms at n=343 and n=393 removed by Georg Fischer, Oct 19 2024]
MATHEMATICA
Select[CatalanNumber[Range[30]], EvenQ] (* Vladimir Reshetnikov, Nov 02 2015 *)
PROG
(PARI) lista(nn) = for (n=1, nn, if (((c=binomial(2*n, n)/(n+1)) % 2) == 0, print1(c, ", "))); \\ Michel Marcus, Nov 02 2015
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Omar E. Pol, Dec 10 2008
STATUS
approved