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A129265 Triangle read by rows: T(n,k) is the number of power of two divisors of n that are less than or equal to n/k.

%I A129265 #20 Jan 27 2021 09:47:00
%S A129265 1,2,1,1,1,1,3,2,1,1,1,1,1,1,1,2,2,2,1,1,1,1,1,1,1,1,1,1,4,3,2,2,1,1,
%T A129265 1,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,3,3,
%U A129265 3,2,2,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1
%N A129265 Triangle read by rows: T(n,k) is the number of power of two divisors of n that are less than or equal to n/k.
%C A129265 Equals A115361 * A000012 as infinite lower triangular matrices (cf. A129264).
%H A129265 Andrew Howroyd, <a href="/A129265/b129265.txt">Table of n, a(n) for n = 1..1275</a>
%F A129265 T(n,k) = 1 for n odd.
%e A129265 First few rows of the triangle are:
%e A129265   1;
%e A129265   2, 1;
%e A129265   1, 1, 1;
%e A129265   3, 2, 1, 1;
%e A129265   1, 1, 1, 1, 1;
%e A129265   2, 2, 2, 1, 1, 1;
%e A129265   1, 1, 1, 1, 1, 1, 1;
%e A129265   ...
%o A129265 (PARI) T(n, k)={sumdiv(n, d, d <= n/k && d==1<<valuation(d, 2))} \\ _Andrew Howroyd_, Aug 07 2018
%Y A129265 Row sums are A129527.
%Y A129265 Column 1 is A001511.
%Y A129265 Cf. A115361, A000012, A129264.
%K A129265 nonn,tabl
%O A129265 1,2
%A A129265 _Gary W. Adamson_, Apr 06 2007
%E A129265 Name changed and terms a(56) and beyond from _Andrew Howroyd_, Aug 07 2018