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A080850 Number triangle related to a problem of Knuth. 0
1, 1, 1, 1, 2, 1, 2, 3, 3, 1, 5, 5, 6, 4, 1, 11, 10, 11, 10, 5, 1, 22, 21, 21, 21, 15, 6, 1, 43, 43, 42, 42, 36, 21, 7, 1, 85, 86, 85, 84, 78, 57, 28, 8, 1, 170, 171, 171, 169, 162, 135, 85, 36, 9, 1, 341, 341, 342, 340, 331, 297, 220, 121, 45, 10, 1, 683, 682, 683, 671, 628, 517 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

In lower-triangular form, the columns are the binomial transforms of the sequences with g.f. x^(k-1)/(1-x^3). The first three columns are A024493, A024494, A024495.

LINKS

Table of n, a(n) for n=1..72.

FORMULA

T(n, 1) = A024493(n). T(n, k)=0, k>n, T(n, n)=1. T(n, k) = T(n-1, k-1)+T(n-1, k).

EXAMPLE

Rows are {1}, {1,1}, {1,2,1}, {2,3,3,1}, {5,5,6,4,1}, {11,10,11,10,5,1}...

CROSSREFS

Sequence in context: A091836 A291980 A238281 * A247453 A109449 A129570

Adjacent sequences:  A080847 A080848 A080849 * A080851 A080852 A080853

KEYWORD

easy,nonn,tabl

AUTHOR

Paul Barry, Feb 20 2003

STATUS

approved

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Last modified February 21 20:03 EST 2020. Contains 332110 sequences. (Running on oeis4.)