%I A131865
%S A131865 1,17,273,4369,69905,1118481,17895697,286331153,4581298449,73300775185,
%T A131865 1172812402961,18764998447377,300239975158033,4803839602528529,
%U A131865 76861433640456465,1229782938247303441,19676527011956855057
%N A131865 Partial sums of powers of 16.
%C A131865 a(n) = if n=0 then 1 else a(n-1)+A001025(n);
%C A131865 for n>0: A131851(a(n))=n and ABS(A131851(m))<n for m<a(n);
%C A131865 a(n) = A098704(n+2)/2.
%C A131865 16=2^4 is the growth measure for the Jacobsthal spiral (compare with 
               phi^4 for the Fibonacci spiral). - Paul Barry (pbarry(AT)wit.ie), 
               Mar 07 2008
%C A131865 Bisection of A115451. - Paul Curtz (bpcrtz(AT)free.fr), May 20 2008
%C A131865 Second quadrisection of A115451. - Paul Curtz (bpcrtz(AT)free.fr), May 
               21 2008
%F A131865 a(n) = (A001025(n+1)-1)/15.
%F A131865 a(n)=16a(n-1)+1. - Paul Curtz (bpcrtz(AT)free.fr), May 20 2008
%F A131865 a(n)=16a(n-1)+1. - Paul Curtz (bpcrtz(AT)free.fr), May 21 2008
%e A131865 a(3) = 1+16+256+4096 = 4369 = in binary: 1000100010001.
%t A131865 Table[(2^(4 n) - 1)/15, {n, 16}] (* Robert G. Wilson v (rgwv(AT)rgwv.com), 
               Aug 22 2007 *)
%o A131865 (Other) sage: [gaussian_binomial(n,1,16) for n in xrange(1,18)] # [From 
               Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), May 28 2009]
%Y A131865 Cf. A000225, A002450, A023001, A132469.
%Y A131865 Sequence in context: A142898 A159678 A097830 this_sequence A031417 A029811 
               A113076
%Y A131865 Adjacent sequences: A131862 A131863 A131864 this_sequence A131866 A131867 
               A131868
%K A131865 nonn
%O A131865 0,2
%A A131865 Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jul 22 2007