A076707 Ordered differences without repetitions between two successive prime powers of prime numbers.

1, 2, 3, 4, 5, 10, 12, 16, 17, 18, 30, 38, 41, 46, 54, 72, 74, 94, 120, 128, 138, 139, 168, 186, 199, 240, 248, 250, 260, 271, 286, 288, 312, 316, 354, 356, 370, 408, 424, 432, 496, 546, 552, 582, 600, 602, 618, 678, 720, 768, 792, 836, 840, 876, 890, 894, 912

Offset

1,2

Comments

Several entries are represented by at least two differences: 4 (which equals 8-4 & 125-121), 168, 312, 600, 768, 792, 912, 1848, 2472, etc.

Links

Table of n, a(n) for n=1..57.

Example

250 = 161051 - 160801 = 11^5 - 401^2.

Mathematica

pp = Sort[ Flatten[ Table[ Prime[n]^Prime[i], {n, 1, PrimePi[ Sqrt[10^16]]}, {i, 1, PrimePi[ Floor[ Log[ Prime[n], 10^16]]]}]]]; l = Length[pp]; b = Take[pp, -l + 1] - Take[pp, l - 1]; Take[ Union[a], 57]

Crossrefs

Cf. A053810, A075308, A077257, A077258.

Sequence in context: A348511 A338897 A296160 * A364902 A382747 A032940

Adjacent sequences: A076704 A076705 A076706 * A076708 A076709 A076710

Keyword

nonn

Author

Zak Seidov, Oct 26 2002

Extensions

Edited and corrected by Robert G. Wilson v, Oct 31 2002

Status

approved