%I A072257
%S A072257 6,15,27,21,597,4437,25941,136533,677205,3233109,15029589,68506965,
%T A072257 307582293,1364546901,5995058517,26127717717,113100805461,486762960213,
%U A072257 2084490794325,8887718991189
%V A072257 -6,-15,-27,21,597,4437,25941,136533,677205,3233109,15029589,68506965,
               307582293,
%W A072257 1364546901,5995058517,26127717717,113100805461,486762960213,2084490794325,
%X A072257 8887718991189
%N A072257 ((6n-17)*4^n-1)/3.
%C A072257 Related to Collatz function (for n>2). All divisible by 3.
%Y A072257 Cf. A072258, A072259, A072260.
%Y A072257 Sequence in context: A008440 A022601 A112150 this_sequence A140091 A165454 
               A063525
%Y A072257 Adjacent sequences: A072254 A072255 A072256 this_sequence A072258 A072259 
               A072260
%K A072257 sign
%O A072257 0,1
%A A072257 rathankar (rathankar(AT)yahoo.com), Jul 08 2002
%E A072257 Edited and extended by Henry Bottomley (se16(AT)btinternet.com), Aug 
               06 2002