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A082904 Triangle read by rows: Pascal's triangle restricted to binomial(n, d) where d is a divisor of n. 0
1, 2, 1, 3, 1, 4, 6, 1, 5, 1, 6, 15, 20, 1, 7, 1, 8, 28, 70, 1, 9, 84, 1, 10, 45, 252, 1, 11, 1, 12, 66, 220, 495, 924, 1, 13, 1, 14, 91, 3432, 1, 15, 455, 3003, 1, 16, 120, 1820, 12870, 1, 17, 1, 18, 153, 816, 18564, 48620, 1, 19, 1, 20, 190, 4845, 15504, 184756, 1, 21, 1330 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..67.

EXAMPLE

n-th row of table consists of A000005(n) terms:

   1;

   2,   1;

   3,   1;

   4,   6,   1;

   5,   1;

   6,  15,  20,   1;

   7,   1;

   8,  28,  70,   1;

   9,  84,   1;

  10,  45, 252,   1;

  ...

25th row = {C(25,1), C(25,5), C(25,25)} = {25, 53130, 1}.

MAPLE

A082904_row := proc(n) seq(binomial(n, d), d=numtheory[divisors](n)) end:

seq(print(A082904_row(n)), n=1..10); # Peter Luschny, Dec 06 2011

MATHEMATICA

Flatten[Table[Binomial[n, Divisors[n]], {n, 1, 25}], 1]

PROG

(PARI) for(n=1, 30, fordiv(n, d, print1(binomial(n, d)", "))) \\ Charles R Greathouse IV, Dec 06 2011

CROSSREFS

Cf. A000005, A007318, A056045.

Sequence in context: A293892 A295885 A329035 * A034868 A050382 A197956

Adjacent sequences:  A082901 A082902 A082903 * A082905 A082906 A082907

KEYWORD

nonn,tabf

AUTHOR

Labos Elemer, Apr 23 2003

EXTENSIONS

New name from Peter Luschny, Dec 06 2011

STATUS

approved

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Last modified July 13 15:18 EDT 2020. Contains 335688 sequences. (Running on oeis4.)