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 A027318 a(n) = Sum_{k=0..m-3} T(n,k) * T(n,k+2), where m=n for n=0,1,2,3; m=2n for n >= 4; and T is given by A026082. 0
 1, 42, 420, 3786, 33648, 297940, 2633872, 23265744, 205446960, 1814136746, 16021697220, 141535810130, 1250763720312, 11057433981126, 97794407702052, 865284559977150, 7659315417653664, 67827407480624862, 600898634852988364, 5325658497658529790 (list; graph; refs; listen; history; text; internal format)
 OFFSET 3,2 LINKS CROSSREFS Sequence in context: A224455 A114928 A127545 * A251425 A242144 A242145 Adjacent sequences: A027315 A027316 A027317 * A027319 A027320 A027321 KEYWORD nonn AUTHOR EXTENSIONS More terms from Sean A. Irvine, Oct 27 2019 STATUS approved

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Last modified November 26 14:22 EST 2022. Contains 358362 sequences. (Running on oeis4.)