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A286938
Length of n-th iterate of the mapping 00->001, 1->10, as in A284932.
5
2, 3, 5, 8, 13, 21, 33, 52, 82, 128, 200, 313, 488, 761, 1188, 1852, 2887, 4503, 7020, 10943, 17063, 26601, 41468, 64652, 100792, 157128, 244965, 381898, 595363, 928166, 1446998, 2255827, 3516797, 5482628, 8547285, 13325053, 20773513, 32385456
OFFSET
0,1
COMMENTS
Appears to be identical to A164457 except for the initial terms 2,3,5.
FORMULA
Conjecture: a(n) = 2*a(n-1) - a(n-2) + 2*a(n-3) -3*a(n-4) + a(n-5) for 5 >= 0.
MATHEMATICA
s = {0, 0}; w[0] = StringJoin[Map[ToString, s]];
w[n_] := StringReplace[w[n - 1], {"00" -> "001", "1" -> "10"}]
Table[w[n], {n, 0, 8}]
st = ToCharacterCode[w[11]] - 48 (* A284932 *)
Flatten[Position[st, 0]] (* A285352 *)
Flatten[Position[st, 1]] (* A285303 *)
Table[StringLength[w[n]], {n, 1, 35}] (* A286938 *)
CROSSREFS
Sequence in context: A283936 A278800 A334738 * A055806 A358902 A023438
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jun 03 2017
STATUS
approved