A050186 Triangular array T read by rows: T(h,k) = number of binary words of k 1's and h-k 0's which are not a juxtaposition of 2 or more identical subwords.
1, 1, 1, 0, 2, 0, 0, 3, 3, 0, 0, 4, 4, 4, 0, 0, 5, 10, 10, 5, 0, 0, 6, 12, 18, 12, 6, 0, 0, 7, 21, 35, 35, 21, 7, 0, 0, 8, 24, 56, 64, 56, 24, 8, 0, 0, 9, 36, 81, 126, 126, 81, 36, 9, 0, 0, 10, 40, 120, 200, 250, 200, 120, 40, 10, 0, 0, 11, 55, 165, 330, 462, 462, 330, 165, 55, 11
Offset: 0
Examples
For example, T(4,2) counts 1100,1001,0011,0110; T(2,1) counts 10, 01 (hence also counts 1010, 0101). Rows: 1; 1, 1; 0, 2, 0; 0, 3, 3, 0; 0, 4, 4, 4, 0; 0, 5, 10, 10, 5, 0;
Links
- M. F. Hasler, A050186, rows 0..50, Sep 27 2018
- M. F. Hasler, A050186, rows 0..100, Sep 27 2018
- M. F. Hasler, A050186, rows 0..200, Sep 27 2018
- N. J. A. Sloane, Transforms
- Index entries for triangles and arrays related to Pascal's triangle
Crossrefs
Programs
-
Mathematica
T[n_, k_] := If[n == 0, 1, DivisorSum[GCD[k, n], MoebiusMu[#] Binomial[n/#, k/#]&]]; Table[T[n, k], {n, 0, 12}, {k, 0, n}] // Flatten (* Jean-François Alcover, Jul 16 2022 *)
-
PARI
A050186(n,k)=sumdiv(gcd(n+!n,k),d,moebius(d)*binomial(n/d,k/d)) \\ M. F. Hasler, Sep 27 2018
Formula
MOEBIUS transform of A007318 Pascal's Triangle.
If rows n > 1 are divided by n, this yields the triangle A051168, which equals A245558 surrounded by 0's (except for initial terms). This differs from A011847 from row n = 9 on. - M. F. Hasler, Sep 29 2018