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A027274 a(n) = Sum_{k=0..2n-2} T(n,k) * T(n,k+2), with T given by A026552. 0
10, 40, 342, 1279, 11016, 41462, 359530, 1365014, 11899516, 45501743, 398306769, 1531614109, 13450930624, 51952990090, 457449811458, 1773182087440, 15646091896400, 60825762159338, 537651887201990, 2095280066101886, 18547910336883720, 72432026278468535 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Table of n, a(n) for n=2..23.

CROSSREFS

Sequence in context: A118266 A054885 A000449 * A253674 A016082 A003355

Adjacent sequences:  A027271 A027272 A027273 * A027275 A027276 A027277

KEYWORD

nonn

AUTHOR

Clark Kimberling

EXTENSIONS

More terms from Sean A. Irvine, Oct 26 2019

STATUS

approved

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Last modified December 5 09:47 EST 2020. Contains 338945 sequences. (Running on oeis4.)