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A104994
Least k(n)>1 such that n*k(n)^2+n*k(n)+1 is a prime > (n-1)*k(n-1)^2+(n-1)*k(n-1)+1 or 0 if n=4 as no prime possible.
1
2, 2, 2, 0, 2, 2, 2, 3, 3, 6, 6, 7, 8, 8, 12, 14, 14, 19, 21, 21, 22, 27, 27, 28, 29, 29, 30, 30, 34, 37, 38, 39, 39, 41, 41, 43, 50, 52, 54, 54, 56
OFFSET
1,1
COMMENTS
sequence of the primes given in A104995
EXAMPLE
1*2^2+1*2+1=7 prime so k(1)=2
2*2^2+2*2+1=13 prime > 7 so k(2)=2
3*2^2+3*2+1=19 prime > 13 so k(3)=2
5*2^2+5*2+1=31 prime > 19 so k(5)=2
CROSSREFS
Cf. A104995.
Sequence in context: A307521 A328995 A036476 * A118664 A223175 A322213
KEYWORD
nonn
AUTHOR
Pierre CAMI, Mar 31 2005
STATUS
approved