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A092105 Primes p such that both p-2 and p-4 are semiprimes. 1
37, 53, 59, 89, 97, 163, 223, 239, 251, 269, 293, 307, 331, 397, 419, 449, 521, 547, 593, 673, 683, 691, 701, 757, 853, 953, 997, 1061, 1103, 1123, 1151, 1171, 1193, 1259, 1319, 1373, 1511, 1531, 1567, 1693, 1783, 1801, 1823, 1931, 1987, 2053, 2161, 2203 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A063638 and A092104.

LINKS

Table of n, a(n) for n=1..48.

EXAMPLE

97 is a member because 95=5*19 and 93=3*31

PROG

(PARI) isok(n) = (n>5) && isprime(n) && (bigomega(n-2) ==  2) && (bigomega(n-4) == 2); \\ Michel Marcus, Oct 05 2013

CROSSREFS

Cf. A063638, A092104.

Sequence in context: A074401 A323476 A345169 * A101938 A060330 A302720

Adjacent sequences:  A092102 A092103 A092104 * A092106 A092107 A092108

KEYWORD

easy,nonn

AUTHOR

Zak Seidov, Feb 20 2004

EXTENSIONS

More terms from Ray Chandler, Feb 21 2004

STATUS

approved

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Last modified December 4 12:52 EST 2021. Contains 349524 sequences. (Running on oeis4.)