A344830 a(n) is the smallest b > 1 such that prime(n), prime(n+1), prime(n+2), prime(n+3), prime(n+4) and prime(n+5) are all base-b Wieferich primes.

132857, 2006776, 296449, 17134811, 36763941, 34998229, 31239565, 968576295, 1027038511, 287811239, 15022368222, 33452659960, 19477999997, 132892045949, 47341045210, 32176849766, 106967760951, 303459122992, 20216391690, 1411108384416, 219517083156, 361244580521, 455588981749

Offset

1,1

Links

Max Alekseyev, Table of n, a(n) for n = 1..100

Prog

(PARI) a(n) = my(v=[prime(n)]); while(#v < 6, 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)))))

Crossrefs

Cf. A039678, A259075. Column 6 of A286816.

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), A344829 (k=4), A344831 (k=6), A344832 (k=7).

Sequence in context: A242327 A339535 A319063 * A015407 A204536 A061732

Adjacent sequences: A344827 A344828 A344829 * A344831 A344832 A344833

Keyword

nonn

Author

Felix Fröhlich, May 29 2021

Extensions

Terms a(10) onward from Max Alekseyev, Oct 10 2023

Status

approved