%I A055274
%S A055274 1,7,56,448,3584,28672,229376,1835008,14680064,117440512,939524096,
%T A055274 7516192768,60129542144,481036337152,3848290697216,30786325577728,
%U A055274 246290604621824,1970324836974592,15762598695796736,126100789566373888
%N A055274 First differences of 8^n (A001018).
%C A055274 For n>=1, a(n) is equal to the number of functions f:{1,2...,n}->{1,2,
               3,4,5,6,7,8} such that for a fixed x in {1,2,...,n} and a fixed y 
               in {1,2,3,4,5,6,7,8} we have f(x)<>y. - Aleksandar M. Janjic and 
               Milan R. Janjic (agnus(AT)blic.net), Mar 27 2007
%D A055274 A. H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, 
               pps. 194-196.
%H A055274 Milan Janjic, <a href="http://www.pmfbl.org/janjic/">Enumerative Formulas 
               for Some Functions on Finite Sets</a>
%F A055274 G.f.: (1-x)/(1-8x). a(n)=7*8^(n-1); a(0)=1. a(n)=8a(n-1)+[(-1)^n]*C(1, 
               1-n).
%Y A055274 Cf. A001018.
%Y A055274 Sequence in context: A092318 A057090 A156362 this_sequence A152776 A155197 
               A147839
%Y A055274 Adjacent sequences: A055271 A055272 A055273 this_sequence A055275 A055276 
               A055277
%K A055274 easy,nonn
%O A055274 0,2
%A A055274 Barry E. Williams, May 28 2000
%E A055274 More terms from James A. Sellers (sellersj(AT)math.psu.edu), May 29 2000