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A100484
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The primes doubled.
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193
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4, 6, 10, 14, 22, 26, 34, 38, 46, 58, 62, 74, 82, 86, 94, 106, 118, 122, 134, 142, 146, 158, 166, 178, 194, 202, 206, 214, 218, 226, 254, 262, 274, 278, 298, 302, 314, 326, 334, 346, 358, 362, 382, 386, 394, 398, 422, 446, 454, 458, 466, 478, 482, 502, 514, 526
(list;
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refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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COMMENTS
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Even semiprimes.
Apart from first term, these are the tau2-primes as defined in [Anderson, Frazier] and [Lanterman]. - Michel Marcus, May 15 2019
For every positive integer b and each m in this sequence b^(m-1) == b (mod m). - Florian Baur, Nov 26 2021
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LINKS
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Eric Weisstein's World of Mathematics, Semiprime
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FORMULA
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MAPLE
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MATHEMATICA
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PROG
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(Haskell)
a100484 n = a100484_list !! (n-1)
a100484_list = map (* 2) a000040_list
(GAP) List([1..70], n-> 2*Primes[n]) # G. C. Greubel, May 18 2019
(Sage) [2*nth_prime(n) for n in (1..70)] # G. C. Greubel, May 18 2019
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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Simpler definition.
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STATUS
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approved
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