A139413 Triangle read by rows: row n gives the numbers A010888(n*k) for k = 1..n.

1, 2, 4, 3, 6, 9, 4, 8, 3, 7, 5, 1, 6, 2, 7, 6, 3, 9, 6, 3, 9, 7, 5, 3, 1, 8, 6, 4, 8, 7, 6, 5, 4, 3, 2, 1, 9, 9, 9, 9, 9, 9, 9, 9, 9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 2, 4, 6, 8, 1, 3, 5, 7, 9, 2, 4, 3, 6, 9, 3, 6, 9, 3, 6, 9, 3, 6, 9, 4

Offset: 1

Author

Philippe Lallouet (philip.lallouet(AT)orange.fr), Apr 19 2008

Keywords

• easy
• nonn
• tabl
• base

Examples

			Triangle begins:
1
2 4
3 6 9
4 8 3 7
5 1 6 2 7
6 3 9 6 3 9
7 5 3 1 8 6 4
8 7 6 5 4 3 2 1
9 9 9 9 9 9 9 9 9
...
		

Links

• Nathaniel Johnston, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A007953 (column 1), A180592 - A180599 (columns 2 - 9), A010888, A038194.

Programs

Maple

A010888:=proc(n) return ((n-1) mod 9)+1; end:
for n from 1 to 9 do for k from 1 to n do printf("%d ",A010888(n*k)); od: printf("\n"): od: # Nathaniel Johnston, Apr 21 2011

Mathematica

Table[FixedPoint[Total@ IntegerDigits[#] &, n k], {n, 13}, {k, n}] // Flatten (* Michael De Vlieger, Oct 31 2021 *)

Extensions

More terms and several terms corrected by Nathaniel Johnston, Apr 21 2011