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A053203
Pascal's triangle (excluding first, last three elements of each row) read by rows, row n read mod n.
5
2, 0, 0, 0, 6, 0, 3, 0, 0, 3, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 4, 3, 0, 0, 0, 3, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 7, 2, 7, 0, 7, 0, 5, 0, 3, 10, 0, 0, 10, 3, 0, 5, 0, 12, 0, 8, 0, 6, 0, 8, 0, 12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 6, 0, 0, 2, 0, 0, 6, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
OFFSET
6,1
COMMENTS
Prime numbered rows contain all zeros.
EXAMPLE
Triangle begins:
2;
0,0;
0,6,0;
3,0,0,3;
0,0,2,0,0;
...
row 9 = 84 mod 9, 126 mod 9, 126 mod 9, 84 mod 9, = 3, 0, 0, 3.
MATHEMATICA
Table[Mod[Binomial[n, k], n], {n, 6, 20}, {k, 3, n-3}] // Flatten (* Jean-François Alcover, Jan 17 2014 *)
PROG
(Haskell)
a053203 n k = a053203_tabl !! (n - 6) !! k
a053203_row n = a053203_tabl !! (n - 6)
a053203_tabl = zipWith (\k row -> take (k - 5) $ drop 3 row)
[6..] $ drop 6 a053200_tabl
-- Reinhard Zumkeller, Jan 24 2014
CROSSREFS
Row sums give A053206.
Cf. A053200, A053201, A053203, A007318 (Pascal's triangle).
Sequence in context: A339016 A262679 A326390 * A158360 A309746 A094315
KEYWORD
nonn,nice,tabl
AUTHOR
Asher Auel, Dec 12 1999
EXTENSIONS
a(30) corrected by T. D. Noe, Feb 08 2008
STATUS
approved