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 A045630 Number of 2n-bead black-white complementable strings with n black beads and fundamental period 2n. 6
 1, 1, 2, 9, 32, 125, 450, 1715, 6400, 24300, 92250, 352715, 1351584, 5200299, 20056582, 77558625, 300533760, 1166803109, 4537542888, 17672631899, 68923172000, 269128935495, 1052049129142, 4116715363799, 16123800483072 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS For n>0, a(n) is divisible by n (cf. A022553), 2*a(n) is divisible by n^2 (cf. A268619), and 12*a(n) is divisible by n^3 (cf. A268592). - Max Alekseyev, Feb 07 2016 LINKS FORMULA Moebius transform of A001700(n-1). - Christian G. Bower. For n>0, a(n) = A007727(n)/2 = n * A022553(n). CROSSREFS Cf. A007727. Sequence in context: A076959 A003697 A006253 * A075364 A026526 A086607 Adjacent sequences:  A045627 A045628 A045629 * A045631 A045632 A045633 KEYWORD nonn AUTHOR STATUS approved

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Last modified August 7 23:38 EDT 2020. Contains 336279 sequences. (Running on oeis4.)