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A229902
a(n) is the smallest m such that 19*m^k+1 is prime for k=1, 2,...,n.
1
10, 10, 10, 2080, 178030, 41697270, 4355942080, 1944616927560
OFFSET
1,1
COMMENTS
10 divides all terms.
MATHEMATICA
a[1]=10; a[n_]:=a[n]=(For[m=a[n-1]/10, Union[Table[PrimeQ[19(10m)^k+1], {k, n}]]=={True}, m++]; 10m) (* Farideh Firoozbakht Oct 05 2013 *)
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Jahangeer Kholdi, Oct 04 2013
EXTENSIONS
a(7) from Farideh Firoozbakht Oct 05 2013
a(8) from Tyler Busby, Jan 06 2023
STATUS
approved