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A064902
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Semiprimes p1*p2 such that p2 mod p1 = 4, with p2 > p1.
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1
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77, 95, 145, 221, 295, 371, 395, 407, 437, 445, 469, 545, 559, 649, 695, 745, 763, 895, 959, 995, 1057, 1133, 1145, 1159, 1195, 1253, 1345, 1351, 1513, 1517, 1679, 1745, 1795, 1841, 1895, 1939, 1945, 2021, 2045, 2095, 2101, 2195, 2245, 2249, 2395, 2429
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OFFSET
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1,1
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LINKS
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PROG
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(Python)
from sympy import factorint
f = factorint(n)
return (sum([f[i] for i in f]) == 2) and (max(f) % min(f) == 4)
x = 1
an = []
while len(an) < n:
n += 2
(PARI) isok(n) = my(f = factor(n)); (#f~ == 2) && (vecmax(f[, 2]) < 2) && ((f[2, 1] % f[1, 1]) == 4); \\ Michel Marcus, Apr 16 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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