cp's OEIS Frontend

A224537 Least odd number d such that the Collatz iteration of d has the following property: if the length of the iteration is b and the maximum value occurs at c, the ratio c/b is the n-th Farey-like fraction.

%I A224537 #5 Apr 23 2013 16:27:24
%S A224537 1,3,5,215,21,1625,13,901,467,771667051
%N A224537 Least odd number d such that the Collatz iteration of d has the following property: if the length of the iteration is b and the maximum value occurs at c, the ratio c/b is the n-th Farey-like fraction.
%C A224537 The Farey-like fractions are 1, 1/2, 1/3, 2/3, 1/4, 3/4, 1/5, 2/5, 3/5, 4/5, 1/6, 5/6,.... The numerators/denominators are in A038566/A038567. We conclude (unsurprisingly) that the maximum value of a Collatz iteration usually appears toward the beginning of the iteration.
%e A224537 Viewed as an irregular triangle, with 0's for unknown terms:
%e A224537 1
%e A224537 3,
%e A224537 5, 215,
%e A224537 21, 1625,
%e A224537 13, 901, 467, 771667051,
%e A224537 53, 0,
%e A224537 67, 35, 1815, 43641, 97, 0,
%e A224537 141, 23, 90435, 0,
%e A224537 93, 79, 15, 895, 763, 0,
%e A224537 61, 603, 1224211, 0,
%e A224537 37, 267, 59, 8857, 5793, 335737, 60221, 5434799, 0, 0
%Y A224537 Cf. A224533.
%K A224537 nonn
%O A224537 1,2
%A A224537 _T. D. Noe_, Apr 23 2013