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 A346603 The first of four solutions to a Monthly problem asking if there exist finite sequences 1 < a(1) < a(2) < ... < a(n) such that Sum_i 1/a(i) = 1 and gcd(a(i), a(i+1)) = 1 for 1 <= i < n. 3
 3, 4, 5, 9, 22, 25, 99, 100 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS There are probably a large number of such sequences, but it seems worthwhile putting these four examples on record. They were the only solutions submitted. LINKS Daniel Ullman, Proposer, Problem E3359, Amer. Math. Monthly, 98:2 (1991), 168. CROSSREFS Cf. A346604, A346605, A346606. Sequence in context: A080552 A215176 A257041 * A056797 A029727 A086186 Adjacent sequences: A346600 A346601 A346602 * A346604 A346605 A346606 KEYWORD nonn,fini,full AUTHOR N. J. A. Sloane, Aug 06 2021 STATUS approved

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Last modified November 29 11:54 EST 2022. Contains 358424 sequences. (Running on oeis4.)