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A144042 Square array A(n,k), n>=1, k>=1, read by antidiagonals, with A(1,k)=1 and sequence a_k of column k shifts left when Euler transform applied k times. 8
1, 1, 1, 1, 1, 2, 1, 1, 3, 4, 1, 1, 4, 8, 9, 1, 1, 5, 13, 25, 20, 1, 1, 6, 19, 51, 77, 48, 1, 1, 7, 26, 89, 197, 258, 115, 1, 1, 8, 34, 141, 410, 828, 871, 286, 1, 1, 9, 43, 209, 751, 2052, 3526, 3049, 719, 1, 1, 10, 53, 295, 1260, 4337, 10440, 15538, 10834, 1842, 1, 1, 11, 64 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,6

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..1035

N. J. A. Sloane, Transforms

EXAMPLE

Square array begins:

1,   1,   1,   1,   1,    1,  ...

1,   1,   1,   1,   1,    1,  ...

2,   3,   4,   5,   6,    7,  ...

4,   8,  13,  19,  26,   34,  ...

9,  25,  51,  89, 141,  209,  ...

20, 77, 197, 410, 751, 1260,  ...

MAPLE

with (numtheory): etr:= proc(p) local b; b:=proc(n) option remember; local d, j; if n=0 then 1 else add (add (d*p(d), d=divisors(j)) *b(n-j), j=1..n)/n fi end end: A:= proc(n, k) local a, b, t; b[1]:= etr(a); for t from 2 to k do b[t]:= etr(b[t-1]) od: a:= n-> `if`(n=1, 1, b[k](n-1)); a(n) end: seq (seq (A(n, d-n), n=1..d-1), d=2..15);

CROSSREFS

Columns 1-9 give: A000081, A007563, A144035, A144036, A144037, A144038, A144039, A144040, A144041. Rows 2-4 give: A000012, A000027, A034856.

Sequence in context: A092422 A096465 A124460 * A122084 A104559 A080853

Adjacent sequences:  A144039 A144040 A144041 * A144043 A144044 A144045

KEYWORD

eigen,nonn,tabl

AUTHOR

Alois P. Heinz (heinz(AT)hs-heilbronn.de), Sep 08 2008

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Last modified February 17 16:49 EST 2012. Contains 206058 sequences.