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 A324333 Numbers d such that A324331(x)=d^2 only when x is a squarefree semiprime (A006881). 3
 1, 2, 4, 6, 11, 12, 14, 16, 18, 20, 21, 22, 24, 25, 27, 29, 30, 32, 34, 35, 36, 38, 39, 41, 42, 43, 44, 45, 47, 50, 51, 52, 53, 54, 56, 57, 58, 59, 60, 64, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 79, 81, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 97, 98, 100 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Problem posed by Albert A. Mullin who asks if this sequence is infinite. LINKS B. Alspach, Research problems, Problem 18, Discrete Math 40 (1982), page 126. CROSSREFS Cf. A000010, A000203, A006881. Cf. A324331, A324334 (complement). Sequence in context: A057661 A237277 A097954 * A081988 A244748 A245017 Adjacent sequences:  A324330 A324331 A324332 * A324334 A324335 A324336 KEYWORD nonn AUTHOR Michel Marcus, Feb 23 2019 STATUS approved

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Last modified September 25 09:26 EDT 2020. Contains 337335 sequences. (Running on oeis4.)