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A330968 Prime numbers p such that 2*p - last digit of p is prime. 0
2, 3, 5, 7, 13, 19, 23, 31, 37, 43, 53, 59, 67, 79, 83, 113, 139, 157, 179, 193, 199, 211, 223, 229, 233, 263, 271, 277, 283, 307, 331, 359, 367, 373, 389, 397, 409, 419, 433, 443, 457, 487, 509, 547, 563, 569, 601, 613, 619, 643, 653, 661, 691, 709, 719, 727 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Prime numbers p such that 2*p - (p mod 10) is prime.

LINKS

Table of n, a(n) for n=1..56.

EXAMPLE

Prime number 19 is a term since 2 * 19 - (19 mod 10) = 2 * 19 - 9 = 29, a prime.

PROG

(PARI) forprime(p = 2, 1000, if(isprime(2*p - p%10), print1(p", ")))

(MAGMA) [p:p in PrimesUpTo(750)| IsPrime(2*p-(p mod 10))]; // Marius A. Burtea, Feb 07 2020

CROSSREFS

Cf. A000040, A007652.

Sequence in context: A233134 A082885 A118371 * A153591 A038917 A124661

Adjacent sequences:  A330965 A330966 A330967 * A330969 A330970 A330971

KEYWORD

nonn,base

AUTHOR

Dimitris Valianatos, Feb 06 2020

STATUS

approved

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Last modified May 25 11:27 EDT 2020. Contains 334592 sequences. (Running on oeis4.)