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A364121
Stolarsky representation of n.
4
0, 1, 11, 10, 111, 101, 110, 1111, 100, 1011, 1101, 1110, 11111, 1010, 1001, 10111, 1100, 11011, 11101, 11110, 111111, 1000, 10101, 10011, 10110, 101111, 11010, 11001, 110111, 11100, 111011, 111101, 111110, 1111111, 10100, 10001, 101011, 10010, 100111, 101101
OFFSET
1,3
FORMULA
Description of an algorithm for calculating a(n):
Let s(1) = {} be the empty set, and for n > 1, let s(n) be the sequence of digits of a(n). s(n) can be calculated recursively by:
1. If n = round(round(n/phi)*phi) then s(n) = s(floor(n/phi^2) + 1) U {0}, where phi is the golden ratio (A001622) and U denotes concatenation.
2. If n != round(round(n/phi)*phi) then s(n) = s(round(n/phi)) U {1}.
a(n) = A007088(A200714(n)).
A268643(a(n)) = A200649(n).
A055641(a(n)) = A200650(n).
A055642(a(n)) = A200648(n).
A043562(a(n)) = A200651(n)
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]]; Array[a, 100]
PROG
(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));
KEYWORD
nonn,base
AUTHOR
Amiram Eldar, Jul 07 2023
STATUS
approved