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A077274
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Differences between two successive powers of a prime but not a prime (A025475) in more than one way.
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0
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4, 7, 17, 408, 792, 912, 1608, 1848, 2472, 2912, 3192, 3288, 3432, 3528, 4008, 4080, 4920, 5160, 5208, 5928, 6072, 6792, 6888, 7080, 7512, 7728, 7800, 8520, 8832, 10632, 10848, 11400, 11880, 11928, 12792, 13200, 13440, 13560, 14280, 14640
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| 4 = 8 - 4 = 125 -121, 7 = 16 - 9 = 32768 - 32761, 17 = 49 - 32 = 81 -64 = 529 - 512, etc.
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MATHEMATICA
| pp = Sort[ Flatten[ Table[ Prime[n]^i, {n, 1, PrimePi[ Sqrt[10^16]]}, {i, 1, Log[ Prime[n], 10^16]]]}]]]; l = Length[pp]; b = Sort[ Take[pp, -l + 1] - Take[pp, l - 1]]; Union[ b[[ Select[ Range[375], b[[ # ]] == b[[ # + 1]] &]]]]
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CROSSREFS
| Cf. A025475.
Sequence in context: A049944 A098091 A057450 * A080650 A005509 A147366
Adjacent sequences: A077271 A077272 A077273 * A077275 A077276 A077277
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KEYWORD
| nonn
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AUTHOR
| Robert G. Wilson v (rgwv(AT)rgwv.com), Oct 31 2002
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