A154234 Triangle read by rows: T(n,k) = (n mod d(k)), where d(i) is the number of divisors of i.

0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 2, 1, 0, 0, 0, 0, 0, 2, 0, 1, 1, 1, 1, 3, 1, 0, 0, 0, 2, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 0, 2, 0, 2, 1, 2, 0, 1, 1, 2, 1, 3, 1, 3, 2, 3, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1

Offset: 1

Author

Juri-Stepan Gerasimov, Nov 26 2010

Keywords

• nonn
• tabl
• easy

Examples

			The first few rows are given by:
0.
0 0.
0 1 1.
0 0 0 1.
0 1 1 2 1.
0 0 0 0 0 2.
0 1 1 1 1 3 1.
0 0 0 2 0 0 0 0.
0 1 1 0 1 1 1 1 0.
0 0 0 1 0 2 0 2 1 2.- _G. C. Greubel_, Sep 06 2016
		

Links

• G. C. Greubel, Table of n, a(n) for the first 50 rows

Crossrefs

Cf. A000005.

Programs

Mathematica

Table[Mod[n,DivisorSigma[0,k]],{n,20},{k,n}]//Flatten (* Harvey P. Dale, Jul 21 2016 *)

PARI

T(n,k)=n%numdiv(k) \\ Charles R Greathouse IV, Sep 07 2016