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A073924
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Smallest power of 2 that is greater than the previous term such that every partial sum (n>1) is a prime.
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7
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OFFSET
| 1,2
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COMMENTS
| Next term 2^1752 is too large to include.
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EXAMPLE
| a(5) is 128 because it is the next power of 2 greater than 16 such that 1+2+4+16+x is prime.
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MATHEMATICA
| a[1] = 1; a[n_] := Block[{k = a[n - 1] + 1, s = Plus @@ (2^Array[a, n - 1])}, While[ !PrimeQ[s + 2^k], k++ ]; k]; Array[2^a[ # ] &, 9] (from Robert G. Wilson v (rgwv(at)rgwv.com), Jan 31 2006)
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CROSSREFS
| Cf. A073923.
Sequence in context: A144526 A179532 A174677 * A061588 A202360 A050472
Adjacent sequences: A073921 A073922 A073923 * A073925 A073926 A073927
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KEYWORD
| nonn
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Aug 19 2002
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EXTENSIONS
| More terms from Jason Earls (zevi_35711(AT)yahoo.com), Sep 03 2002
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