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A158902 Triangle read by rows: the matrix product A051731 * A158821. 4
1, 2, 1, 3, 0, 1, 5, 1, 0, 1, 5, 0, 0, 0, 1, 9, 1, 1, 0, 0, 1, 7, 0, 0, 0, 0, 0, 1, 12, 1, 0, 1, 0, 0, 0, 1, 11, 0, 1, 0, 0, 0, 0, 0, 1, 15, 1, 0, 0, 1, 0, 0, 0, 0, 1, 11, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 23, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
T(n,n) = 1.
T(n,1) = A158901(n).
EXAMPLE
First few rows of the triangle =
1;
2, 1;
3, 0, 1;
5, 1, 0, 1;
5, 0, 0, 0, 1;
9, 1, 1, 0, 0, 1;
7, 0, 0, 0, 0, 0, 1;
12, 1, 0, 1, 0, 0, 0, 1
11, 0, 1, 0, 0, 0, 0, 0, 1;
15, 1, 0, 0, 1, 0, 0, 0, 0, 1;
11, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;
23, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1;
13, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;
21, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1;
...
MAPLE
A158902 := proc(n, k)
add( A051731(n, j)*A158821(j-1, k-1), j=k..n) ;
end proc:
seq(seq(A158902(n, k), k=1..n), n=1..12) ; # R. J. Mathar, Jan 08 2015
MATHEMATICA
m = 12; (* number of rows *)
T1[n_, k_] := Boole[Mod[n, k] == 0];
T2[n_, k_] := Which[n == k, 1, k == 1, n-1, True, 0];
T = Array[T1, {m, m}].Array[T2, {m, m}];
Table[T[[n, k]], {n, m}, {k, n}] // Flatten (* Jean-François Alcover, Feb 01 2023 *)
CROSSREFS
Cf. A158821, A051731, A158901, A000203 (row sums).
Sequence in context: A113287 A195665 A096798 * A137587 A168021 A137639
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson and Mats Granvik, Mar 29 2009
EXTENSIONS
Wrong A-number in definition corrected by Robert Israel, Jan 08 2015
STATUS
approved

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Last modified April 18 22:18 EDT 2024. Contains 371782 sequences. (Running on oeis4.)