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A109217
a(n) is the binary string of length n+1 that has 0's at indices that are squares and 1's elsewhere, where the most significant digit has index 0.
2
0, 0, 1, 11, 110, 1101, 11011, 110111, 1101111, 11011110, 110111101, 1101111011, 11011110111, 110111101111, 1101111011111, 11011110111111, 110111101111110, 1101111011111101, 11011110111111011, 110111101111110111, 1101111011111101111, 11011110111111011111
OFFSET
0,4
LINKS
EXAMPLE
110111101 is a term because the string '00110111101' has zeros at the square indices 0,1,4,9 and the first two zeros are dropped.
MATHEMATICA
With[{s = Array[Boole[! IntegerQ@ Sqrt@ #] &, 1002, 0]}, Array[FromDigits[s[[1 ;; #]] ] &, Length@ s]] (* Michael De Vlieger, Mar 23 2020 *)
PROG
(PARI) a(n) = fromdigits(vector(n, i, !issquare(i))); \\ Jinyuan Wang, Mar 22 2020
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Jason Earls, Jun 22 2005
EXTENSIONS
Name changed, several terms inserted, and one more term from Jinyuan Wang, Mar 22 2020
STATUS
approved