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A144856 Semiprimes that are a product of distinct Mersenne primes. 4
21, 93, 217, 381, 889, 3937, 24573, 57337, 253921, 393213, 917497, 1040257, 1572861, 3670009, 4063201, 16252897, 16646017, 66584449, 1073602561, 4294434817, 6442450941, 15032385529, 66571993057, 68718821377, 272730423169 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

T. D. Noe, Table of n, a(n) for n=1..90

Prime Curios!

MATHEMATICA

Mp = 2^{2, 3, 5, 7, 13, 17, 19, 31, 61} - 1; Take[ Union[ Times @@@ Subsets[ Mp, {2}]], 25] (* Robert G. Wilson v, Sep 25 2008 *)

CROSSREFS

Cf. A000668, A001358.

Sequence in context: A143843 A119109 A254603 * A065522 A218844 A219423

Adjacent sequences:  A144853 A144854 A144855 * A144857 A144858 A144859

KEYWORD

nonn

AUTHOR

G. L. Honaker, Jr., Sep 22 2008

EXTENSIONS

More terms from Robert G. Wilson v, Sep 25 2008

More terms from T. D. Noe, Sep 25 2008

STATUS

approved

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Last modified January 23 12:31 EST 2021. Contains 340385 sequences. (Running on oeis4.)