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A091490 Primes p such that all prime divisors of p^2 + p + 1 are less than p. 0
67, 79, 137, 149, 163, 181, 191, 211, 229, 263, 269, 277, 313, 373, 431, 439, 499, 521, 571, 631, 653, 787, 809, 811, 821, 823, 919, 947, 971, 991, 997, 1049, 1069, 1087, 1109, 1129, 1153, 1231, 1237, 1283, 1291, 1367, 1429, 1451, 1459, 1471, 1493, 1511 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..48.

Simon Davis, A Proof of the Odd Perfect Number Conjecture, arXiv:hep-th/0401052

MATHEMATICA

PrimeFactors[ n_Integer ] := Flatten[ Table[ #[ [ 1 ] ], {1} ] & /@ FactorInteger[ n ] ]; Prime[ Select[ Range[ 242 ], Prime[ # ] > PrimeFactors[ Prime[ # ]^2 + Prime[ # ] + 1 ][ [ -1 ] ] & ] ]

CROSSREFS

Cf. A073501.

Sequence in context: A106930 A106929 A173040 * A091075 A139973 A118741

Adjacent sequences:  A091487 A091488 A091489 * A091491 A091492 A091493

KEYWORD

nonn

AUTHOR

R. K. Guy and Robert G. Wilson v, Jan 14 2004

EXTENSIONS

Replaced arXiv URL by non-cached version - R. J. Mathar, Oct 30 2009

STATUS

approved

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Last modified November 24 04:08 EST 2014. Contains 249867 sequences.