OFFSET
0,3
COMMENTS
a(n) = T(n,n), as defined in A083291.
LINKS
N. J. A. Sloane, Table of n, a(n) for n = 0..10000
Index entries for linear recurrences with constant coefficients, signature (1, 0, 0, 0, 0, 0, 0, 0, 0, 2, -2, 0, 0, 0, 0, 0, 0, 0, 0, -1, 1).
FORMULA
a(n)= +a(n-1) +2*a(n-10) -2*a(n-11) -a(n-20) +a(n-21). - R. J. Mathar, Feb 20 2011
EXAMPLE
a(25) = 25*2 + 5 = 55.
MATHEMATICA
Table[n Floor[n/10]+Mod[n, 10], {n, 0, 70}] (* or *) LinearRecurrence[ {1, 0, 0, 0, 0, 0, 0, 0, 0, 2, -2, 0, 0, 0, 0, 0, 0, 0, 0, -1, 1}, {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 40}, 70] (* Harvey P. Dale, May 23 2015 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Reinhard Zumkeller, Apr 23 2003
STATUS
approved