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A123346 Mirror image of the Bell triangle A011971, which is also called the Pierce triangle or Aitken's array. 2
1, 2, 1, 5, 3, 2, 15, 10, 7, 5, 52, 37, 27, 20, 15, 203, 151, 114, 87, 67, 52, 877, 674, 523, 409, 322, 255, 203, 4140, 3263, 2589, 2066, 1657, 1335, 1080, 877, 21147, 17007, 13744, 11155, 9089, 7432, 6097, 5017, 4140, 115975, 94828, 77821, 64077, 52922 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,2

REFERENCES

D. E. Knuth, The Art of Computer Programming, vol. 4A, Combinatorial Algorithms, Section 7.2.1.5 (p. 418).

LINKS

Eric Weisstein's World of Mathematics, Bell Triangle.

FORMULA

a(n,k) = Sum_{i=k..n} binomial(n-k,i-k)*Bell(i). - Vladeta Jovovic (vladeta(AT)eunet.rs), Oct 14 2006

EXAMPLE

Triangle begins:

1

2 1

5 3 2

15 10 7 5

52 37 27 20 15

203 151 114 87 67 52

CROSSREFS

Cf. A011971. Borders give Bell numbers A000110. Diagonals give A005493, A011965, A011966, A011968, A011969, A046934, A011972, A094577, A095149, A106436, A108041, A108042, A108043.

Sequence in context: A067418 A067323 A106534 * A163840 A122833 A193692

Adjacent sequences:  A123343 A123344 A123345 * A123347 A123348 A123349

KEYWORD

nonn,tabl

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Oct 14 2006

EXTENSIONS

More terms from Alexander Adamchuk (alex(AT)kolmogorov.com) and Vladeta Jovovic (vladeta(AT)eunet.rs), Oct 14 2006

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Last modified February 16 01:56 EST 2012. Contains 205860 sequences.