OFFSET
4,1
COMMENTS
Previous name was: First number in row n of triangle A199636.
LINKS
Robert G. Wilson v, Table of n, a(n) for n = 4..573 (first 500 terms from T. D. Noe)
MATHEMATICA
Collatz[n_] := NestWhileList[If[EvenQ[#], #/2, 3 # + 1] &, n, # > 1 &]; nn = 100; t = Table[0, {nn}]; cnt = 3; n = 1; While[cnt < nn, n = n + 2; len = Length[Select[Collatz[n], EvenQ]]; If[len <= nn && t[[len]] == 0, t[[len]] = n; cnt++]]; t
f = Compile[{{n, _Real}}, Block[{c = 0, k = n}, While[k > 1, c++; If[OddQ@ Round@ k, k = (3k + 1)/2, k /= 2]]; c]]; k = 1; t[_] := 0; While[k < 2101, If[t@ f@ k == 0, t@ f@ k = k; ]; k += 2]; t@# & /@ Range@ 100 (* Robert G. Wilson v, Mar 06 2018 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
T. D. Noe, Nov 14 2011
EXTENSIONS
New name from Robert G. Wilson v, Mar 06 2018
STATUS
approved