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A283773
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Numbers k such that U(k) = 1 mod 3, where U = A001950 = upper Wythoff sequence.
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3
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3, 4, 5, 11, 12, 13, 19, 20, 27, 28, 35, 36, 42, 43, 44, 50, 51, 52, 58, 59, 60, 66, 67, 68, 74, 75, 82, 83, 90, 91, 97, 98, 99, 105, 106, 107, 113, 114, 115, 121, 122, 123, 129, 130, 137, 138, 144, 145, 146, 152, 153, 154, 160, 161, 162, 168, 169, 170, 176
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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a(n+1) - a(n) is in {1,6,7} for every n.
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MATHEMATICA
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r = GoldenRatio^2; z = 350; t = Table[Floor[n*r], {n, 1, z}]; u = Mod[t, 3];
Flatten[Position[u, 0]] (* A283772 *)
Flatten[Position[u, 1]] (* A283773 *)
Flatten[Position[u, 2]] (* A283774 *)
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PROG
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(PARI) r = (3 + sqrt(5))/2;
for(n=1, 351, if(floor(n*r)%3==1, print1(n, ", "))) \\ Indranil Ghosh, Mar 19 2017
(Python)
import math
from sympy import sqrt
r = (3 + sqrt(5))/2
[n for n in range(1, 351) if int(math.floor(n*r))%3==1] # Indranil Ghosh, Mar 19 2017
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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