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A247955 Primes p such that there is prime q with sigma(q+2) = p. 0
7, 13, 31, 1093, 2801, 5113, 8011, 17293, 30103, 30941, 86143, 459007, 552793, 579883, 732541, 1191373, 3500201, 3730693, 4534771, 5168803, 5333791, 7450171, 10378063, 25646167, 25882657, 28792661, 30266503, 43553401, 48037081, 52265671, 56964757, 62433703, 65504743, 76413823 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes p such that there is prime q such that A000203(q+2) = p.

Primes p of the form sigma(A171130(n)) in increasing order.

LINKS

Table of n, a(n) for n=1..34.

PROG

(PARI) v=[]; forprime(p=1, 10^8, if(ispseudoprime(sigma(p+2)), v=concat(v, sigma(p+2)))); v \\ Derek Orr, Oct 26 2014

CROSSREFS

Cf. A000203, A008438, A171130, A247791, A247820, A247821, A247822, A247823, A247954.

Sequence in context: A195353 A247178 A053183 * A026318 A061204 A060983

Adjacent sequences:  A247952 A247953 A247954 * A247956 A247957 A247958

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Sep 28 2014

EXTENSIONS

More terms from Michel Marcus, Oct 02 2014

STATUS

approved

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Last modified July 20 11:28 EDT 2019. Contains 325180 sequences. (Running on oeis4.)