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A200714
Stolarsky representation interpreted as binary to decimal integers.
11
0, 1, 3, 2, 7, 5, 6, 15, 4, 11, 13, 14, 31, 10, 9, 23, 12, 27, 29, 30, 63, 8, 21, 19, 22, 47, 26, 25, 55, 28, 59, 61, 62, 127, 20, 17, 43, 18, 39, 45, 46, 95, 24, 53, 51, 54, 111, 58, 57, 119, 60, 123, 125, 126, 255, 16, 41, 35, 42, 87, 37, 38, 79, 44, 91, 93
OFFSET
1,3
COMMENTS
See explanation of Stolarsky representations in the C. Mongoven link.
FORMULA
From Amiram Eldar, Jul 07 2023: (Start)
A000120(a(n)) = A200649(n).
A023416(a(n)) = A200650(n).
A070939(a(n)) = A200648(n).
A005811(a(n)) = A200651(n). (End)
Conjecture: a(n) = A367306(A358654(n-1)). - Mikhail Kurkov, Oct 17 2024
EXAMPLE
The Stolarsky representation of 19 is 11101. In binary this is equal to 29. So a(19) = 29.
MATHEMATICA
stol[n_] := stol[n] = If[n == 1, {}, If[n != Round[Round[n/GoldenRatio]*GoldenRatio], Join[stol[Floor[n/GoldenRatio^2] + 1], {0}], Join[stol[Round[n/GoldenRatio]], {1}]]];
a[n_] := FromDigits[stol[n], 2]; Array[a, 100] (* Amiram Eldar, Jul 07 2023 *)
PROG
(PARI) a(n) = {if (n == 1, return (0)); tau = (1 + sqrt(5))/2; mn = 0; while ((m = round(mn*tau)) < n, mn++; ); if (m == n, return (2*a(mn)+1)); mn = 0; while ((m = floor(mn*(1+tau)-tau/2)) < n, mn++; ); if (m == n, return (2*a(mn))); error("neither A nor B !!"); } \\ (cf C. Mongoven link) Michel Marcus, May 21 2013, Sep 02 2013
(PARI) stol(n) = {my(phi=quadgen(5)); if(n==1, [], if(n != round(round(n/phi)*phi), concat(stol(floor(n/phi^2) + 1), [0]), concat(stol(round(n/phi)), [1]))); }
a(n) = fromdigits(stol(n), 2); \\ Amiram Eldar, Jul 07 2023
KEYWORD
nonn,base
AUTHOR
Casey Mongoven, Nov 20 2011
EXTENSIONS
More terms from Amiram Eldar, Jul 07 2023
STATUS
approved