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%I #5 Mar 30 2012 17:30:50
%S 1,2,3,4,5,10,12,16,17,18,30,38,41,46,54,72,74,94,120,128,138,139,168,
%T 186,199,240,248,250,260,271,286,288,312,316,354,356,370,408,424,432,
%U 496,546,552,582,600,602,618,678,720,768,792,836,840,876,890,894,912
%N Ordered differences without repetitions between two successive prime powers of prime numbers.
%C 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.
%e 250 = 161051 - 160801 = 11^5 - 401^2.
%t 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]
%Y Cf. A053810, A075308, A077257, A077258.
%K nonn
%O 1,2
%A _Zak Seidov_, Oct 26 2002
%E Edited and corrected by _Robert G. Wilson v_, Oct 31 2002