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A260594
a(n) is the least k such that A260590(k) = A260593(n).
1
1, 2, 3, 5, 13, 15, 19, 23, 35, 45, 51, 55, 63, 77, 79, 83, 95, 115, 119, 125, 141, 143, 179, 255, 319, 335, 351, 435, 463, 495, 527, 653, 791, 819, 847, 909, 1023, 1143, 1699, 1715, 2127, 2295, 3191, 3197, 3443, 3639, 3763, 3981, 5043, 6199, 6719, 7519, 8845
OFFSET
1,2
COMMENTS
This is the index corresponding to, or responsible for, A260593.
EXAMPLE
13 is the least k such that A260590(k) = 59 = A260593(5), so a(5) = 13.
MATHEMATICA
msa[n_] := If[ OddQ@ n, (3n + 1)/2, n/2]; f[n_] := Block[{k = 2n + 1}, Length@ NestWhileList[ msa@# &, k, # >= k &] - 1]; k = 1; lst = lsu = {}; While[k < 10000001, a = f@ k; If[ !MemberQ[lst, a], AppendTo[lst, a]; AppendTo[lsu, k]]; k++]; lsu
CROSSREFS
Sequence in context: A145343 A058592 A268509 * A228940 A045311 A356196
KEYWORD
nonn,easy
AUTHOR
Joseph K. Horn and Robert G. Wilson v, Aug 30 2015
STATUS
approved