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%I #38 Dec 30 2022 06:36:57
%S 1,2,3,10,24,25,66,168,182,186,187,188,438,6462,40071,40084,40085,
%T 40091,40108,40118,251745,637224,637306,637336,637338,10553441,
%U 10553445,10553452,10553479,10553515,10553550,10553829,27067032,27067054,27067134,69709710,69709713,179992838,179993008
%N Numbers k such that prime(k+1) == 1 (mod k).
%C If k is a term, then prime(k+1)^prime(k+1) is a reverse Meertens number in base prime(k+1)^((prime(k+1)-1)/k). - _Chai Wah Wu_, Dec 14 2022
%C Integers k such that A004649(k+1) = 1. - _Michel Marcus_, Dec 30 2022
%H Chai Wah Wu, <a href="http://arxiv.org/abs/1603.08493">Meertens Number and Its Variations</a>, arXiv:1603.08493 [math.NT], 2016.
%H Chai Wah Wu, <a href="https://research.library.kutztown.edu/contact/vol3/iss1/5">Meertens number and its variations</a>, Communications on Number Theory and Combinatorial Theory, 3 (2022), article 5.
%t bb={};Do[If[1==Mod[Prime[n+1], n], bb=Append[bb, n]], {n, 1, 200000}];bb
%o (Sage)
%o def A105286(max) :
%o terms = []
%o p = 3
%o for n in range(1, max+1) :
%o if (p - 1) % n == 0 : terms.append(n)
%o p = next_prime(p)
%o return terms
%o # _Eric M. Schmidt_, Feb 05 2013
%o (Python)
%o from itertools import count, islice
%o from sympy import prime
%o def A105286_gen(startvalue=1): # generator of terms >= startvalue
%o return filter(lambda k: not (prime(k+1)-1)%k,count(max(startvalue,1)))
%o A105286_list = list(islice(A105286_gen(),10)) # _Chai Wah Wu_, Dec 14 2022
%Y Cf. A004649, A105287, A105288, A105290, A105329, A105451.
%K nonn
%O 1,2
%A _Zak Seidov_, Apr 25 2005
%E More terms from _Farideh Firoozbakht_, May 12 2005
%E First term inserted by _Eric M. Schmidt_, Feb 05 2013
%E More terms from _Michel Marcus_, Dec 29 2022
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