OFFSET
0,10
COMMENTS
REFERENCES
D. E. Knuth, The Art of Computer Programming, vol. 4A, Combinatorial Algorithms, Section 7.2.1.3, Eq. (20), p. 360.
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 0..10000
FORMULA
EXAMPLE
First triangle: [0]; second triangle: [0; 0 1]; third triangle: [0; 0 1; 0 1 2]; ...
MAPLE
seq(seq(seq(i, i=0..k), k=0..n), n=0..6); # Peter Luschny, Sep 22 2011
MATHEMATICA
Table[i, {k, 0, 7}, {j, 0, k}, {i, 0, j}] // Flatten (* Robert G. Wilson v, Sep 27 2011 *)
PROG
(Haskell)
import Data.List (inits)
a056558 n = a056558_list !! n
a056558_list = concatMap (concat . init . inits . enumFromTo 0) [0..]
-- Reinhard Zumkeller, Jun 01 2015
(PARI) T(t, n, k)=k \\ Charles R Greathouse IV, Feb 22 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Henry Bottomley, Jun 26 2000
STATUS
approved