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 A369000 a(n) is the number of integers, not semiprimes, whose arithmetic derivative is equal to the n-th primorial. 7
 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 2, 9, 18 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,11 COMMENTS a(n) = number of solutions k to equation A003415(k) = A002110(n) with A001222(k) > 2. LINKS Table of n, a(n) for n=1..13. Antti Karttunen, PARI-program Index entries for sequences related to primorial numbers FORMULA a(n) = A351029(n) - A116979(n). PROG (PARI) \\ See the attached PARI-program. CROSSREFS Cf. A001222, A002110, A003415, A116979, A351029, A366890 (solutions themselves). Sequence in context: A083707 A240651 A357432 * A346102 A346233 A358946 Adjacent sequences: A368997 A368998 A368999 * A369001 A369002 A369003 KEYWORD nonn,hard,more AUTHOR Antti Karttunen, Jan 16 2024 STATUS approved

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Last modified August 13 02:23 EDT 2024. Contains 375113 sequences. (Running on oeis4.)