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 A291634 Number of primitive sequences n = b_1 < b_2 < ... < b_t = A006255(n) such that b_1*b_2*...*b_t is a perfect square. 0
 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 3, 1, 1, 1, 8, 1, 11, 1, 1, 2, 20, 1, 1, 2, 1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,11 COMMENTS A primitive sequence is one such that no proper, nonempty subsequence has a product that is a perfect square. Trivially, a(n) <= A259527(n). If A259527(n) = 1, then a(n) = 1. LINKS MAPLE For n = 22 the a(22) = 2 solutions are: 22 * 24 * 33 = 132^2, and 22 * 27 * 32 * 33 = 792^2. Note that 22 * 24 * 25 * 33 = 660^2 is not a solution because the subsequence [25] has a square product. CROSSREFS Cf. A006255, A259527. Sequence in context: A274613 A066975 A355879 * A098877 A225212 A091088 Adjacent sequences: A291631 A291632 A291633 * A291635 A291636 A291637 KEYWORD nonn,more AUTHOR Peter Kagey, Aug 29 2017 STATUS approved

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Last modified December 7 17:25 EST 2022. Contains 358668 sequences. (Running on oeis4.)