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 A131910 Central terms of triangle A131909. 1
 1, 1, 3, 8, 26, 79, 274, 964, 3496, 12664, 46157, 168240, 615173, 2256669, 8321911, 30871862, 115280183, 433247309, 1638036186, 6225871432, 23769249188, 91077899373, 350002189936, 1348065993111, 5201249282212, 20094668668700 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Table of n, a(n) for n=0..25. FORMULA a(n) = A131909(2n,n) for n>=0. PROG (PARI) CROSSREFS Cf. A131909. Sequence in context: A317852 A306485 A148801 * A205775 A331320 A148802 Adjacent sequences: A131907 A131908 A131909 * A131911 A131912 A131913 KEYWORD nonn AUTHOR Paul D. Hanna, Jul 26 2007 STATUS approved

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Last modified December 3 17:32 EST 2023. Contains 367540 sequences. (Running on oeis4.)