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 A210455 Characteristic function of pseudoperfect (or semiperfect) numbers. 7
 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1 COMMENTS a(A005835(n)) = 1 and a(A136447(n)) = 0. LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 Eric Weisstein's World of Mathematics, Semiperfect Number Wikipedia, Semiperfect number PROG (Haskell) a210455 n = fromEnum \$ p (a027751_row n) n where    p ks m = m == 0 || not (null ks) && head ks <= m &&             (p (tail ks) (m - head ks) || p (tail ks) m) CROSSREFS Cf. A027751. Sequence in context: A093958 A044936 A133944 * A294936 A296210 A094912 Adjacent sequences:  A210452 A210453 A210454 * A210456 A210457 A210458 KEYWORD nonn AUTHOR Reinhard Zumkeller, Jan 21 2013 STATUS approved

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Last modified May 16 08:07 EDT 2021. Contains 343940 sequences. (Running on oeis4.)