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A137781
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a(n) = (2^prime(n) + 2^prime(n+1)) / 4.
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2
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3, 10, 40, 544, 2560, 34816, 163840, 2228224, 136314880, 671088640, 34896609280, 584115552256, 2748779069440, 37383395344384, 2286984185774080, 146366987889541120, 720575940379279360, 37469948899722526720, 627189298506124754944
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OFFSET
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1,1
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COMMENTS
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Note that 4 is 2^prime(1).
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LINKS
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FORMULA
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MAPLE
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MATHEMATICA
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Table[(2^Prime[n] + 2^Prime[n + 1])/4, {n, 20}] (* Wesley Ivan Hurt, Mar 27 2015 *)
(2^#[[1]]+2^#[[2]])/4&/@Partition[Prime[Range[20]], 2, 1] (* Harvey P. Dale, Dec 21 2019 *)
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PROG
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(Magma) [(2^NthPrime(n) + 2^NthPrime(n+1)) / 4: n in [1..20]]; // Vincenzo Librandi, Mar 28 2015
(PARI) vector(15, n, (2^prime(n)+2^prime(n+1))/4) \\ Derek Orr, Mar 29 2015
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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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STATUS
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approved
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