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A248901 Numbers k such that A248891(k) = 1. 3
1, 2, 3, 4, 5, 20, 29, 30, 2059, 5987, 7119, 20165, 151819, 14984624, 105181798 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

If k is in {1, 2, 3, 4, 29, ...} then both numbers k and k+1 are in the sequence.

LINKS

Table of n, a(n) for n=1..15.

PROG

(PARI) lista(nn) = {my(c=0, q=r=5, s=3, t); forprime(p=9, nn, if(p-2==q, if((t=s^(1+1/c++))>r && t<q, print1(c, ", ")); s=r; r=q); q=p); } \\ Jinyuan Wang, Nov 28 2020

CROSSREFS

Cf. A001359, A248891, A248902, A248903.

Sequence in context: A329579 A024635 A217679 * A280849 A037400 A080695

Adjacent sequences:  A248898 A248899 A248900 * A248902 A248903 A248904

KEYWORD

nonn,more

AUTHOR

Jahangeer Kholdi and Farideh Firoozbakht, Nov 22 2014

EXTENSIONS

a(13)-a(15) from Jinyuan Wang, Nov 28 2020

STATUS

approved

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Last modified September 26 20:34 EDT 2021. Contains 347672 sequences. (Running on oeis4.)