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%I #10 Oct 10 2023 12:14:43
%S 557,1207,1451,13543,24675,39016,217682,165407,1357748,399254,1146590,
%T 325346,1895206,3365181,4674177,21251205,40698745,6795147,36463448,
%U 12717474,54383927,7411274,35989426,101112784,86045167,13128506,276293632,169093089,223680564,137073637
%N a(n) is the smallest b > 1 such that prime(n), prime(n+1), prime(n+2) and prime(n+3) are all base-b Wieferich primes.
%H Max Alekseyev, <a href="/A344828/b344828.txt">Table of n, a(n) for n = 1..100</a>
%o (PARI) a(n) = my(v=[prime(n)]); while(#v < 4, v=concat(v, nextprime(v[#v]+1))); for(b=2, oo, for(k=1, #v, if(Mod(b, v[k]^2)^(v[k]-1)!=1, break, if(k==#v, return(b)))))
%Y Cf. A039678, A259075. Column 4 of A286816.
%Y Cf. smallest b > 1 such that prime(n+i) is a base-b Wieferich prime for each i = 0..k: A039678 (k=0), A259075 (k=1), A344827 (k=2), A344829 (k=4), A344830 (k=5), A344831 (k=6), A344832 (k=7).
%K nonn
%O 1,1
%A _Felix Fröhlich_, May 29 2021
%E Terms a(24) onward from _Max Alekseyev_, Oct 10 2023
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