OFFSET
1,1
COMMENTS
Conjecture: for every n their exists k < n (apart from a(1)) such that k*n+(n-1) is prime. See A034693.
LINKS
Eric W. Weisstein, MathWorld: Linnik's Theorem
Wikipedia, Linnik's theorem.
EXAMPLE
If n=13, the smallest prime in the sequence 25,38,51,64,77,90,103,... is 103, so a(13)=7.
MATHEMATICA
q[n_]:=(k=0; While[!PrimeQ[++k*n+n-1]]; k); Table[q[n], {n, 1, 100}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Frank M Jackson, Oct 05 2011
STATUS
approved