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A160358 Indices of primes in A133547, i.e., numbers n such that the sum of the squares of the first n odd primes is prime. 1
3, 5, 9, 11, 23, 29, 63, 65, 71, 95, 141, 159, 161, 173, 179, 183, 209, 219, 255, 299, 323, 341, 365, 371, 389, 393, 453, 485, 521, 567, 579, 605, 623, 633, 635, 639, 677, 701, 711, 723, 725, 747, 785, 827, 867, 945, 981, 993, 999, 1001, 1013, 1035, 1037, 1041 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms are necessarily odd. Thus one could also consider the sequence floor(a(n)/2) = (1,2,4,5,11,14,31,32,35,...). Other possible variations would be to list the index a(n)+1 of the largest prime in that sum, or, since this is always even, (a(n)+1)/2 = (2,3,5,6,12,15,32,33,36,...).

LINKS

Table of n, a(n) for n=1..54.

FORMULA

A160359(n) = A133547(a(n)) = A024450(a(n)+1) - 4.

PROG

(PARI) s=0; for( i=2, 1999, isprime(s+=prime(i)^2) & print1(i-1, ", "))

CROSSREFS

Cf. A098561, A133547.

Sequence in context: A092917 A256220 A163778 * A319084 A120806 A020946

Adjacent sequences:  A160355 A160356 A160357 * A160359 A160360 A160361

KEYWORD

nonn

AUTHOR

M. F. Hasler, May 18 2009

STATUS

approved

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Last modified November 15 19:54 EST 2018. Contains 317240 sequences. (Running on oeis4.)