OFFSET
1,2
COMMENTS
Let T(n) denote the n-th triangular number. If i, j are any two successive elements of the above sequence then (T(i-1) + T(j-1))/T(i+j-1) = 9/11.
LINKS
FORMULA
MATHEMATICA
a[1] = 1; a[2] = 10; a[n_] := a[n] = 9a[n - 1] - a[n - 2] + 1; Table[ a[n], {n, 20}] (* Robert G. Wilson v, Apr 05 2004 *)
LinearRecurrence[{10, -10, 1}, {1, 10, 90}, 20] (* Harvey P. Dale, May 21 2023 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
M. N. Deshpande (dpratap_ngp(AT)sancharnet.in), Apr 04 2004
EXTENSIONS
More terms from Robert G. Wilson v, Apr 05 2004
Chebyshev comments from Wolfdieter Lang, Aug 31 2004
STATUS
approved