A137757 - OEIS

%I #7 Jun 22 2013 16:06:10

%S 2,2,3,6,5,3,4,12,7,12,7,4,5,20,9,30,31,20,9,5,6,30,11,60,49,60,49,30,

%T 11,6,7,42,13,105,71,140,209,105,71,42,13,7,8,56,15,168,97,280,351,

%U 280,351,168,97,56,15,8,9,72,17,252,127,504,545,630,1471

%N Nontrivial elements in writing the denominator of an element first and then the numerator of that element (left to right) of Leibniz's harmonic-like triangle. That is, the nontrivial elements of A137753.

%e 1/1; -->

%e 1/2, 1/2; --> 2 2

%e 1/3, 5/6, 1/3; --> 3 6 5 3

%e 1/4, 7/12, 7/12, 1/4; --> ...

%e 1/5, 9/20, 31/30, 9/20, 1/5;

%Y Cf. A003506; A007622; A046201; A046204; A046205; A046206; A046208; A046212; A137752; A137753; A137754; A137755; A137756.

%K frac,nonn,tabf,less

%O 1,1

%A _Mohammad K. Azarian_, Feb 10 2008