A127640 Triangle read by rows in which row n contains n-1 0's followed by prime(n).

2, 0, 3, 0, 0, 5, 0, 0, 0, 7, 0, 0, 0, 0, 11, 0, 0, 0, 0, 0, 13, 0, 0, 0, 0, 0, 0, 17, 0, 0, 0, 0, 0, 0, 0, 19, 0, 0, 0, 0, 0, 0, 0, 0, 23, 0, 0, 0, 0, 0, 0, 0, 0, 0, 29, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 31, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 37, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 41, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0

Offset: 1

Author

Gary W. Adamson, Jan 21 2007

Keywords

• nonn
• tabl
• easy

Comments

A127641 = this sequence * A051731.

Examples

			First few rows of the triangle are:
2;
0, 3
0, 0, 5;
0, 0, 0, 7;
0, 0, 0, 0, 11;
...
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A127641, A127638, A127639, A051731.

Programs

Maple

A127640 := proc(n,m) if m < n then 0; else ithprime(n) ; fi ; end: for n from 1 to 15 do for m from 1 to n do printf("%d,",A127640(n,m)) ; od ; od ; # R. J. Mathar, May 19 2007

Mathematica

Table[PadLeft[{Prime[n]},n,0],{n,15}]//Flatten (* Harvey P. Dale, Feb 28 2025 *)

Extensions

More terms from R. J. Mathar, May 19 2007