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A285677 -id:A285677 - OEIS
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Positions of 2 in A285677.
+20
4
3, 5, 10, 12, 17, 22, 24, 29, 31, 36, 41, 43, 48, 53, 55, 60, 62, 67, 72, 74, 79, 81, 86, 91, 93, 98, 103, 105, 110, 112, 117, 122, 124, 129, 134, 136, 141, 143, 148, 153, 155, 160, 162, 167, 172, 174, 179, 184, 186, 191, 193, 198, 203, 205, 210, 212, 217
OFFSET
1,1
COMMENTS
A 3-way partition of the positive integers, by positions of 0, 1, 2 in A285677:
A285678: positions of 0; slope t = (4+sqrt(5))/2;
A182761: positions of 1; slope u = (7-sqrt(5))/2;
A285679: positions of 2; slope v = (1+3*sqrt(5))/2;
where 1/t + 1/u + 1/v = 1.
Conjecture: a(n) - a(n-1) is in {2,5} for n>=2.
See A285683 for a proof of this conjecture. - Michel Dekking, Oct 09 2018
a(n) = A285683(n-1) for n>1, see A285683 for a proof. - Michel Dekking, Oct 09 2018
LINKS
FORMULA
a(n) = 3*floor((n-1)*phi) - n + 4
MATHEMATICA
s = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {0}}] &, {0}, 13] ; (* A003849 *)
w = StringJoin[Map[ToString, s]]
w1 = StringReplace[w, {"0010" -> "2"}]
st = ToCharacterCode[w1] - 48; (* A285677 *)
Flatten[Position[st, 0]]; (* A285678 *)
Flatten[Position[st, 1]]; (* A182761 *)
Flatten[Position[st, 2]]; (* A285679 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 11 2017
STATUS
approved
Positions of 0 in A285677.
+20
3
1, 6, 8, 13, 15, 18, 20, 25, 27, 32, 34, 37, 39, 44, 46, 49, 51, 56, 58, 63, 65, 68, 70, 75, 77, 82, 84, 87, 89, 94, 96, 99, 101, 106, 108, 113, 115, 118, 120, 125, 127, 130, 132, 137, 139, 144, 146, 149, 151, 156, 158, 163, 165, 168, 170, 175, 177, 180, 182
OFFSET
1,2
COMMENTS
A 3-way partition of the positive integers, by positions of 0, 1, 2 in A285677:
A285678: positions of 0; slope t = (4+sqrt(5))/2;
A182761: positions of 1; slope u = (7-sqrt(5))/2;
A285679: positions of 2; slope v = (1+3*sqrt(5))/2;
where 1/t + 1/u + 1/v = 1. Conjecture: a(n) - a(n-1) is in {2,3,4,5} for n>=2.
LINKS
MATHEMATICA
s = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {0}}] &, {0}, 13] ; (* A003849 *)
w = StringJoin[Map[ToString, s]]
w1 = StringReplace[w, {"0010" -> "2"}]
st = ToCharacterCode[w1] - 48; (* A285677 *)
Flatten[Position[st, 0]]; (* A285678 *)
Flatten[Position[st, 1]]; (* A182761 *)
Flatten[Position[st, 2]]; (* A285679 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 11 2017
STATUS
approved
{1010->2}-transform of the infinite Fibonacci word A003849.
+10
4
0, 1, 0, 0, 2, 0, 1, 0, 0, 2, 0, 2, 0, 1, 0, 0, 2, 0, 1, 0, 0, 2, 0, 2, 0, 1, 0, 0, 2, 0, 2, 0, 1, 0, 0, 2, 0, 1, 0, 0, 2, 0, 2, 0, 1, 0, 0, 2, 0, 1, 0, 0, 2, 0, 2, 0, 1, 0, 0, 2, 0, 2, 0, 1, 0, 0, 2, 0, 1, 0, 0, 2, 0, 2, 0, 1, 0, 0, 2, 0, 2, 0, 1, 0, 0, 2
OFFSET
1,5
LINKS
EXAMPLE
As a word, A003849 = 01001010010010100..., and replacing each 1010 by 2 gives 01002010020201002010020201002020100201...
MATHEMATICA
s = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {0}}] &, {0}, 13] ; (* A003849 *)
w = StringJoin[Map[ToString, s]]
w1 = StringReplace[w, {"1010" -> "2"}]
st = ToCharacterCode[w1] - 48; (* A285680 *)
Flatten[Position[st, 0]]; (* A285681 *)
Flatten[Position[st, 1]]; (* A285682 *)
Flatten[Position[st, 2]]; (* A285683 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 11 2017
STATUS
approved

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