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A114874
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Numbers representable in exactly two ways as (p-1)p^k (where p is a prime and k>=0) in ascending order.
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1
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2, 4, 6, 16, 18, 42, 100, 156, 162, 256, 486, 1458, 2028, 4422, 6162, 14406, 19182, 22650, 23548, 26406, 37056, 39366, 62500, 65536, 77658, 113232, 121452, 143262, 208392, 292140, 342732, 375156, 412806, 527802, 564898, 590592, 697048, 843642
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| 6 is a member because 6=(3-1).3^1=(7-1).7^0 and 3 and 7 are primes.
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MATHEMATICA
| s = Split@Sort@Flatten@Table[(Prime[n] - 1)Prime[n]^k, {n, 68000}, {k, 0, 16}]; Union@Flatten@Select[s, Length@# == 2 &] (* Robert G. Wilson v *)
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CROSSREFS
| Cf. A114871, A114873.
Sequence in context: A037019 A096174 A096173 * A100361 A069654 A000068
Adjacent sequences: A114871 A114872 A114873 * A114875 A114876 A114877
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KEYWORD
| nonn
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AUTHOR
| Franz Vrabec (franz.vrabec(AT)aon.at), Jan 03 2006
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EXTENSIONS
| a(13)-a(38) from Robert G. Wilson v (rgwv(at)rgwv.com), Jan 05 2006
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