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A231575 Indices of prime tribonacci numbers (A001590). 54
4, 5, 7, 9, 25, 29, 49, 79, 1613, 15205 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(11) > 2*10^5.

LINKS

Table of n, a(n) for n=1..10.

PROG

(PARI) v=[1, 0, 1]; for(n=4, 1e4, if(ispseudoprime(t=v[1]+v[2]+v[3]), print1(n", ")); v=[v[2], v[3], t]) \\ Charles R Greathouse IV, Nov 18 2013

CROSSREFS

Cf. A001590, A231574, A000213, A056816, A157611.

Sequence in context: A234257 A278335 A243300 * A153085 A047259 A287658

Adjacent sequences:  A231572 A231573 A231574 * A231576 A231577 A231578

KEYWORD

nonn

AUTHOR

Robert Price, Nov 18 2013

STATUS

approved

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Last modified January 29 07:03 EST 2020. Contains 331337 sequences. (Running on oeis4.)