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A209270 a(1) = 2 and, for n >= 2, a(n) is the least integer such that the numerator of the continued fraction [a(1),a(2),...,a(n)] is prime. 0
2, 1, 1, 2, 2, 4, 6, 8, 4, 6, 38, 10, 14, 16, 6, 2, 12, 24, 100, 36, 74, 46, 44, 52, 18, 8, 46, 114, 20, 70, 6, 38, 190, 44, 76, 14, 118, 218, 34, 14, 82, 32, 28, 110, 76, 126, 230, 46, 578, 138, 192, 306, 424, 38, 148, 468, 218, 210, 174, 300, 244, 60, 744, 482 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..64.

PROG

(PARI) v=[2]; for(k=1, 70, m=1; while(isprime(contfracpnqn(concat(v, [m]))[1, 1])==0, m++); v=concat(v, [m])); a(n)=if(n<2, 2, v[n]);

CROSSREFS

Sequence in context: A045870 A229037 A036863 * A083698 A128976 A199627

Adjacent sequences:  A209267 A209268 A209269 * A209271 A209272 A209273

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Jan 15 2013

STATUS

approved

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Last modified October 23 01:24 EDT 2018. Contains 316518 sequences. (Running on oeis4.)