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A178416 Primes p such that q*p+-Mod(p,q) are primes, for q=8. 1
107, 163, 443, 467, 1307, 3163, 3467, 3907, 4283, 5507, 5563, 5923, 6067, 6323, 6427, 8147, 8563, 11083, 11587, 12347, 12763, 14747, 16987, 18443, 18947, 19963, 23227, 24043, 24107, 25867, 26227, 26683, 26987, 27827, 28867, 30347, 31123, 31907, 32843, 33427, 33563 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Each term yields a pair of sexy primes, i.e., {3541, 3547}, {3733, 3739}, etc. - K. D. Bajpai, Oct 05 2020

LINKS

K. D. Bajpai, Table of n, a(n) for n = 1..10000

EXAMPLE

8*107=856 and 856 +/-3 are primes.

From K. D. Bajpai, Oct 05 2020: (Start)

443 is a term because 443 is prime: 8*443 + Mod (443, 8) = 3547 and 8*443 - Mod (443, 8) = 3541 are also prime.

467 is a term because 467 is prime: 8*467 + Mod (467, 8) = 3739 and 8*467 - Mod (467, 8) = 3733 are also prime.

(End)

MAPLE

q:=8: select(p->isprime(p) and isprime(q*p + modp(p, q)) and isprime(q*p - modp(p, q)), [$1..8!]); # K. D. Bajpai, Oct 05 2020

MATHEMATICA

q=8; lst={}; Do[p=Prime[n]; If[PrimeQ[q*p-Mod[p, q]]&&PrimeQ[q*p+Mod[p, q]], AppendTo[lst, p]], {n, 8!}]; lst

q=8; Select[Prime[Range[5000]], AllTrue[q*# + {Mod[#, q], - Mod[#, q]}, PrimeQ] &] (* K. D. Bajpai, Oct 05 2020 *)

PROG

(PARI) q=8; forprime(p=1, 5e4, if(isprime(q*p +(p%q)) && isprime(q*p - (p%q)) , print1(p, ", "))) \\ K. D. Bajpai, Oct 05 2020

(MAGMA) [p: p in PrimesUpTo(50000) | IsPrime(q*p - p mod q) and IsPrime(q*p + p mod q) where q is 8]; // K. D. Bajpai, Oct 05 2020

CROSSREFS

Cf. A000040, A178383, A178385, A178386, A178387.

Sequence in context: A251145 A168475 A142662 * A182477 A229570 A107215

Adjacent sequences:  A178413 A178414 A178415 * A178417 A178418 A178419

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, May 27 2010

EXTENSIONS

a(39)-a(41) from K. D. Bajpai, Oct 05 2020

STATUS

approved

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Last modified December 1 21:42 EST 2020. Contains 338858 sequences. (Running on oeis4.)