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A064908 Semiprimes p1*p2 such that p2 mod p1 = 10, with p2 > p1. 1
299, 473, 551, 1037, 1199, 1271, 1273, 1313, 1441, 1651, 1739, 1817, 2167, 2279, 2327, 2651, 2771, 2813, 2893, 3193, 3341, 3349, 3377, 3439, 3679, 4103, 4331, 4829, 4883, 5071, 5707, 5977, 6049, 6059, 6239, 6281, 6383, 6523, 6817, 7031, 7037, 7097 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

John Cerkan, Table of n, a(n) for n = 1..10000

PROG

(Python)

from sympy import factorint

def is_A064908(n):

    f = factorint(n)

    return (sum([f[i] for i in f]) == 2) and (max(f) % min(f) == 10) # John Cerkan, Apr 14 2018

(PARI) isok(n) = my(f = factor(n)); (#f~ == 2) && (vecmax(f[, 2]) < 2) && ((f[2, 1] % f[1, 1]) == 10); \\ Michel Marcus, Apr 16 2018

CROSSREFS

Cf. A001358 (p2 mod p1 = 0), A064899-A064911.

Sequence in context: A249296 A245956 A235229 * A341189 A105990 A160484

Adjacent sequences:  A064905 A064906 A064907 * A064909 A064910 A064911

KEYWORD

nonn

AUTHOR

Patrick De Geest, Oct 13 2001

EXTENSIONS

Offset changed by John Cerkan, Apr 12 2018

STATUS

approved

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Last modified September 17 16:32 EDT 2021. Contains 347487 sequences. (Running on oeis4.)