A182974 Numbers n for which A020652(n)/A038567(n) = A182972(n)/A182973(n).

1, 2, 7, 158, 1617, 6211, 8058, 16765, 69093, 465988, 5297983, 6546724, 18588348, 38244610, 204136352, 430712111, 2760559191, 100878516991, 440393924631

Offset

1,2

Comments

Numerators of the matching fractions are given in A182975.

Denominators of the matching fractions are given in A182976.

The initial (zeroth) term of A038567 is ignored.

References

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.

Links

Table of n, a(n) for n=1..19.

Paul Yiu, Recreational Mathematics, 24.3.1 Appendix: Two enumerations of the rational numbers in (0,1), page 633.

Example

a(1)=1, a(2)=2 and a(3)=7 because the 1st, 2nd and 7th fractions match in the following two sequences:
1/2, 1/3, 2/3, 1/4, 3/4, 1/5, 2/5, 3/5 ... (A020652/A038567)
1/2, 1/3, 1/4, 2/3, 1/5, 1/6, 2/5, 3/4 ... (A182972/A182973)

Crossrefs

Cf. A020652, A038567, A182972, A182973, A182975, A182976.

Sequence in context: A376470 A207139 A064607 * A005345 A174366 A177798

Adjacent sequences: A182971 A182972 A182973 * A182975 A182976 A182977

Keyword

nonn,more

Author

William Rex Marshall, Dec 16 2010

Status

approved