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 A328585 Numbers n for which A257993(n) is equal to A257993(A276086(A276086(n))), where A276086 converts the primorial base expansion of n into its prime product form, and A257993 returns the index of the least prime not present in its argument. 9
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 OFFSET 1,2 COMMENTS Numbers n for which A257993(n) is equal to A328578(n). All odd numbers are included, as A257993(2n+1) = A328578(2n+1) = 1 for all n >= 0. LINKS Antti Karttunen, Table of n, a(n) for n = 1..10000 PROG (PARI) A257993(n) = { for(i=1, oo, if(n%prime(i), return(i))); } A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); }; A328578(n) = A257993(A276086(A276086(n))); isA328585(n) = (A328578(n) == A257993(n)); CROSSREFS Union of A005408 (odd numbers) and A328586 (even terms). Positions of zeros in A328590. Cf. A257993, A276086, A328578, A328587, A328588. Cf. also A328316, A328317. Sequence in context: A047584 A229089 A277573 * A072153 A206929 A331546 Adjacent sequences: A328582 A328583 A328584 * A328586 A328587 A328588 KEYWORD nonn AUTHOR Antti Karttunen, Oct 21 2019 STATUS approved

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Last modified November 27 07:59 EST 2022. Contains 358362 sequences. (Running on oeis4.)