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A347765
a(n) is the concatenation of terms in the n-th row of triangle A237048.
2
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
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
Sequence in context: A086100 A182782 A217789 * A004283 A376165 A344367
KEYWORD
nonn,base
AUTHOR
Omar E. Pol, Sep 12 2021
STATUS
approved