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A143509
First of a pair of twin primes of the form n^2+x with x<2*n, or 0 if no such prime exist.
1
2, 5, 11, 17, 29, 41, 59, 71, 0, 107, 137, 149, 179, 197, 227, 269, 311, 347, 0, 419, 461, 521, 569, 599, 641, 0, 0, 809, 857, 0, 1019, 1031, 1091, 0, 1277, 1301, 1427, 1451, 0, 1607, 1697, 1787, 1871, 1949, 2027, 2129, 2237, 2309, 0, 2549, 2657, 2711, 0, 2969
OFFSET
1,1
EXAMPLE
1^2+1=2 x=1, x<2*1 and 2 and 3 twin primes so a(1)=2
2^2+1=5 x=1, x<2*2 and 5 and 7 twin primes so a(2)=5
3^2+2=11 x=2, x<2*3 and 11 and 13 twin primes so a(3)=11
CROSSREFS
Cf. A091592.
Sequence in context: A124850 A156850 A156611 * A111166 A064337 A076873
KEYWORD
nonn
AUTHOR
Pierre CAMI, Aug 21 2008
STATUS
approved