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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
1, 3, 5, 6, 7, 9, 11, 13, 15, 17, 18, 19, 21, 23, 25, 27, 29, 31, 33, 35, 36, 37, 39, 41, 43, 45, 47, 48, 49, 51, 53, 55, 57, 59, 61, 63, 65, 66, 67, 69, 71, 73, 75, 77, 78, 79, 81, 83, 85, 87, 89, 91, 93, 95, 96, 97, 99, 101, 103, 105, 107, 108, 109, 111, 113, 115, 117, 119, 121, 123, 125, 126, 127, 129, 131, 133, 135, 137, 138, 139 (list; graph; refs; listen; history; text; internal format)
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

Index entries for sequences related to primorial base

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.)