OFFSET
1,3
COMMENTS
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..10000
Michael De Vlieger, Bitmap of the first 2^10 terms, showing 1s in black, 12X horizontal exaggeration.
Michael De Vlieger, Bitmap of the first 2^12 terms, showing 1s in black, rotated 90 degrees counterclockwise. [Click "magnify" to see the graph more clearly.]
EXAMPLE
The 15th row of the triangle A237048 is [1, 1, 1, 0, 1] and the concatenation of these terms is 11101 which can be interpreted as a binary number whose decimal value is 29, so a(15) = 29.
MATHEMATICA
Table[FromDigits[Boole[Divisible[n - If[OddQ[#], 0, Quotient[#, 2]], #]] & /@ Range[Quotient[Sqrt[8 n + 1] - 1, 2]], 2], {n, 66}] (* Jan Mangaldan, Sep 13 2021 *)
PROG
(PARI) t(n, k) = if (k % 2, (n % k) == 0, ((n - k/2) % k) == 0);
a(n) = fromdigits(vector(floor((sqrt(1+8*n)-1)/2), k, t(n, k)), 2); \\ Michel Marcus, Sep 12 2021
CROSSREFS
KEYWORD
AUTHOR
Omar E. Pol, Sep 06 2021
STATUS
approved