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A077273
Ordered differences without repetitions between two successive powers of a prime but not a prime (A025475).
2
1, 2, 3, 4, 5, 7, 9, 10, 12, 13, 15, 17, 18, 30, 33, 38, 40, 41, 54, 63, 74, 94, 96, 104, 112, 120, 128, 138, 139, 151, 168, 186, 192, 199, 240, 248, 250, 255, 260, 271, 286, 288, 298, 307, 312, 316, 320, 354, 356, 362, 375, 393, 408, 423, 424, 432, 496, 504, 513
OFFSET
1,2
EXAMPLE
33 = 546 - 513 = 2568 - 2535 = 6168 - 6135 = 458703 - 458670 = 885465 - 885432 = 1048608 - 1048575 = 6291480 - 6291447 = 37748688 - 37748655 = 125829345 - 125829312.
MATHEMATICA
pp = Sort[ Flatten[ Table[ Prime[n]^i, {n, 1, PrimePi[ Sqrt[10^16]]}, {i, 1, Log[ Prime[n], 10^16]}]]]; l = Length[pp]; d = Sort[Take[pp, -l + 1] - Take[pp, l - 1]]; Union[ Take[d, 10^5]]
CROSSREFS
Cf. A025475.
Sequence in context: A123538 A092999 A077154 * A032955 A375581 A320848
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Oct 31 2002
STATUS
approved