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A176619 Primes p such that 2p + 3, 4p + 9, 3p + 2 and 9p + 8 are also primes. 0
5, 7, 97, 167, 397, 607, 2617, 2707, 7687, 12097, 14407, 16787, 19577, 22307, 23827, 24967, 25717, 28547, 31687, 43037, 43517, 46817, 58967, 59617, 63607, 70237, 70957, 78517, 85027, 96797 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

These primes stay prime under two iterations of p->2p+3 as well as under two iterations of p->3p+2.

For all entries >5 the least significant digit is 7.

REFERENCES

Joe Buhler: Algorithmic Number Theory: Third International Symposium, ANTS-III, Springer New York, 1998

F. Ischebeck: Einladung zur Zahlentheorie, B. I. Wissenschaftsverlag, Mannheim-Leipzig-Wien-Zuerich, 1992

LINKS

Table of n, a(n) for n=1..30.

FORMULA

A023242 INTERSECT A023246.

EXAMPLE

2*5 + 3 = 13 = prime(6),

4*5 + 9 = 29 = prime(10),

3*5 + 2 = 17 = prime(7),

9*5 + 8 = 53 = prime(16); 5 = prime(3) = a(1).

PROG

(MAGMA) [p: p in PrimesUpTo(100000)|IsPrime(2*p+3) and IsPrime(4*p+9) and IsPrime(3*p+2) and IsPrime(9*p+8 )] // Vincenzo Librandi, Jan 29 2011

CROSSREFS

Cf. A000040, A005602, A023242, A023246, A059762.

Sequence in context: A196139 A165784 A329006 * A230379 A292847 A088270

Adjacent sequences:  A176616 A176617 A176618 * A176620 A176621 A176622

KEYWORD

nonn

AUTHOR

Ulrich Krug (leuchtfeuer37(AT)gmx.de), Apr 22 2010

STATUS

approved

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Last modified April 15 03:00 EDT 2021. Contains 342974 sequences. (Running on oeis4.)