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A306401 The smallest integer k | 2^k + 1 such that omega(k) = n. 0
1, 3, 171, 97641, 143239347, 626958621819 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Conjecture: a(n) | a(n+1).

If the conjecture is right, then a(6) = 5519116747872657, a(7) = 50428169725312467009, a(8) = 2073253341916771456141017, a(9) = 163345411049596672714982306379, a(10) = 14245516643046375424146321921618969.

LINKS

Table of n, a(n) for n=0..5.

PROG

(PARI) v = readvec("v006521.txt");

a(n) = {k=1; while(omega(v[k]) != n, k++); v[k]; };

(PARI) a(n) = my(m=1); while((Mod(2, m)^m!=-1) || (omega(m)!=n), m++); m; \\ Michel Marcus, Feb 16 2019

CROSSREFS

Cf. A006521, A001221 (omega).

Sequence in context: A119117 A136473 A209804 * A053930 A053920 A297948

Adjacent sequences:  A306398 A306399 A306400 * A306402 A306403 A306404

KEYWORD

nonn,more

AUTHOR

Jinyuan Wang, Feb 15 2019

STATUS

approved

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Last modified October 23 16:20 EDT 2021. Contains 348215 sequences. (Running on oeis4.)