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A241959 Primes p such that p+2, p+4, p+6, p+8, p+10 are semiprimes. 1
211, 1381, 3089, 5087, 10399, 18803, 26903, 27031, 31583, 41161, 47189, 49081, 53759, 62939, 63949, 76801, 87383, 93739, 98491, 107509, 109397, 113341, 128099, 143093, 158699, 182747, 186889, 193727, 197507, 201413, 204331, 209477, 239087, 252949, 255989, 256079 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Each term in the sequence is prime p which yields 5 semiprimes in arithmetic progression with common difference of 2.

LINKS

K. D. Bajpai, Table of n, a(n) for n = 1..500

EXAMPLE

a(1) = 211 is prime: 213, 215, 217, 219 and 221 are semiprimes.

a(2) = 1381 is prime: 1383, 1385, 1387, 1389 and 1391 are semiprimes.

MAPLE

with(numtheory): A241959:= proc() local p; p:=ithprime(x); if  bigomega(p+2)=2 and bigomega(p+4)=2 and bigomega(p+6)=2 and bigomega(p+8)=2 and bigomega(p+10)=2 then RETURN (p); fi; end: seq(A241959 (), x=1..100000);

CROSSREFS

Cf. A001358, A082919, A092128, A241483.

Sequence in context: A308798 A104299 A032632 * A179595 A137872 A053072

Adjacent sequences:  A241956 A241957 A241958 * A241960 A241961 A241962

KEYWORD

nonn

AUTHOR

K. D. Bajpai, May 03 2014

STATUS

approved

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Last modified January 29 14:07 EST 2020. Contains 331338 sequences. (Running on oeis4.)