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Numerators of fractions with the same position in A020652/A038567 and A182972/A182973.
4

%I #10 Mar 30 2012 18:39:49

%S 1,1,2,9,30,59,67,97,197,513,1729,1922,3239,4646,10734,15592,39474,

%T 238623,498579

%N Numerators of fractions with the same position in A020652/A038567 and A182972/A182973.

%C The positions of the matching fractions are given in A182974.

%C The denominators of the matching fractions are given in A182976.

%C The initial (zeroth) term of A038567 is ignored.

%D S. Cook, Problem 511: An Enumeration Problem, Journal of Recreational Mathematics, Vol. 9:2 (1976-77), 137. Solution by the Problem Editor, JRM, Vol. 10:2 (1977-78), 122-123.

%H Paul Yiu, <a href="http://math.fau.edu/Yiu/RecreationalMathematics2003.pdf">Recreational Mathematics</a>, 24.3.1 Appendix: Two enumerations of the rational numbers in (0,1), page 633.

%e The matching fractions are 1/2, 1/3, 2/5, 9/23, 30/73, 59/143 ... (this is A182975/A182976).

%Y Cf. A020652, A038567, A182972-A182974, A182976.

%K nonn,frac,more

%O 1,3

%A _William Rex Marshall_, Dec 16 2010