cp's OEIS Frontend

A134188 a(0)=1. a(n) = the sum of the terms of the sequence (from among terms a(0) through a(n-1)) which equal any "non-isolated divisors" of (2n). A divisor, k, of n is non-isolated if (k-1) or (k+1) also divides n.

%I A134188 #8 Apr 09 2014 10:16:32
%S A134188 1,1,2,4,4,4,16,4,4,4,28,4,32,4,4,4,4,4,52,4,56,4,4,4,68,4,4,4,4,4,88,
%T A134188 4,4,4,4,4,108,4,4,4,120,4,124,4,4,4,4,4,144,4,148,4,4,4,160,4,4,4,4,
%U A134188 4,180,4,4,4,4,4,200,4,4,4,212,4,216,4,4,4,4,4,236,4,240,4,4,4,252,4,4,4
%N A134188 a(0)=1. a(n) = the sum of the terms of the sequence (from among terms a(0) through a(n-1)) which equal any "non-isolated divisors" of (2n). A divisor, k, of n is non-isolated if (k-1) or (k+1) also divides n.
%e A134188 The positive divisors of 2*12=24 are 1,2,3,4,6,8,12,24. Of these, 1,2,3,4 are the non-isolated divisors of 24. There are 2 terms among the earlier terms of the sequence that equal 1, 1 term that equals 2, 0 terms that equal 3 and 7 terms that equal 4. So a(12) = 2*1 +1*2 + 0*3 +7*4 = 32.
%Y A134188 Cf. A134187.
%K A134188 nonn
%O A134188 0,3
%A A134188 _Leroy Quet_, Oct 12 2007
%E A134188 Extended by _Ray Chandler_, Jun 25 2008