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%I #13 Oct 11 2023 03:57:17
%S 19601,54568,13543,296449,3414284,14380864,3727271,7916603,65097619,
%T 13793462,152541840,30495845,91779237,183068599,558175167,40698745,
%U 825287029,2151529020,6271678163,1266687934,3149182509,989067909,10785363668,18739432977,4877709531,24531035970,11683733786,52383593584
%N a(n) is the smallest b > 1 such that prime(n), prime(n+1), prime(n+2), prime(n+3) and prime(n+4) are all base-b Wieferich primes.
%H Max Alekseyev, <a href="/A344829/b344829.txt">Table of n, a(n) for n = 1..100</a>
%o (PARI) a(n) = my(v=[prime(n)]); while(#v < 5, 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 5 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), A344828 (k=3), A344830 (k=5), A344831 (k=6), A344832 (k=7).
%K nonn
%O 1,1
%A _Felix Fröhlich_, May 29 2021
%E Terms a(22) onward from _Max Alekseyev_, Oct 10 2023