A347765 a(n) is the concatenation of terms in the n-th row of triangle A237048.

1, 1, 11, 10, 11, 101, 110, 100, 111, 1001, 1100, 1010, 1100, 1001, 11101, 10000, 11000, 10110, 11000, 10001, 111001, 100100, 110000, 101000, 110010, 100100, 111001, 1000001, 1100000, 1011100, 1100000, 1000000, 1110010, 1001000, 1100101, 10100001, 11000000, 10010000, 11100100

Offset

1,3

Comments

The number of ones in a(n) equals A001227(n).

The number of zeros in a(n) equals A238005(n).

The number of digits in a(n) equals A003056(n).

Therefore A238005(n) = A003056(n) - A001227(n).

For further information see theorem A in A238005.

For a nice bitmap see A347266.

Links

Michael De Vlieger, Table of n, a(n) for n = 1..10000

Mathematica

Table[FromDigits@ Map[If[OddQ[#], Boole[Mod[n, #] == 0], Boole[Mod[n - #/2, #] == 0]] &, Range@ Floor[(Sqrt[8 n + 1] - 1)/2]], {n, 39}] (* Michael De Vlieger, Sep 15 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)), 10); \\ Michel Marcus, Sep 12 2021

Crossrefs

Cf. A003056, A007088, A001227, A196020, A237048, A237593, A238005, A347266 (decimal value).

Sequence in context: A086100 A182782 A217789 * A004283 A344367 A106421

Adjacent sequences: A347762 A347763 A347764 * A347766 A347767 A347768

Keyword

nonn,base

Author

Omar E. Pol, Sep 12 2021

Status

approved