A180175 Diagonal sums of A164844.

1, 10, 101, 1011, 10112, 101123, 1011235, 10112358, 101123593, 1011235951, 10112359544, 101123595495, 1011235955039, 10112359550534, 101123595505573, 1011235955056107, 10112359550561680, 101123595505617787, 1011235955056179467, 10112359550561797254

Offset: 1

Author

Mark Dols, Aug 15 2010

Keywords

• nonn
• easy

Comments

Sums are built along inclined lines through the triangle with (1,2)-steps in the (row,column) indices. - R. J. Mathar, Aug 19 2010

Examples

			From _R. J. Mathar_, Aug 19 2010: (Start)
One example is a(5), the sum of numbers in parentheses:
  1;
  1, 10;
  (1), 11, 100;
  1, 12, (111) ; 1000;;
  1, 13, 123 ; 1111, (10000); (End)
		

Links

• Index entries for linear recurrences with constant coefficients, signature (11,-9,-10).

Crossrefs

Cf. A022100, A164844.

Formula

From R. J. Mathar, Aug 19 2010: (Start)

G.f.: ( 1-x ) / ( (10*x-1)*(x^2+x-1) ).

a(n) = +11*a(n-1) -9*a(n-2) -10*a(n-3).

a(n) = (90*10^n -A022100(n))/89. (End)

Extensions

More terms from R. J. Mathar, Aug 19 2010