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A305849
Positions of 2 in the difference sequence of A305847.
3
3, 6, 9, 11, 14, 17, 19, 22, 25, 27, 30, 32, 35, 38, 40, 43, 46, 48, 51, 53, 56, 59, 61, 64, 67, 69, 72, 74, 77, 80, 82, 85, 87, 90, 93, 95, 98, 101, 103, 106, 108, 111, 114, 116, 119, 122, 124, 127, 129, 132, 135, 137, 140, 142, 145, 148, 150, 153, 156, 158
OFFSET
1,1
COMMENTS
This is also the sequence of positions of 3 in the difference sequence of A305848.
LINKS
EXAMPLE
A305837 = (1,2,3,5,6,7,9,10,11,13,14,16, ...);
differences: (1, 1, 2, 1, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 1, 2, 1, 2, ...);
positions of 2: (3,6,9,11,14, ...).
MATHEMATICA
mex[list_, start_] := (NestWhile[# + 1 &, start, MemberQ[list, #] &]);
u = 5; v = 5; z = 220;
c = {v}; a = {1}; b = {Last[c] - Last[a]};
Do[AppendTo[a, mex[Flatten[{a, b}], Last[a]]];
AppendTo[c, u Length[c] + v];
AppendTo[b, Last[c] - Last[a]], {z}];
c = Flatten[Position[Differences[a], 2]];
a (* A305847 *)
b (* A305848 *)
c (* A305849 *)
(* Peter J. C. Moses, May 30 2018 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jun 11 2018
STATUS
approved