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A053200 Binomial coefficients C(n,k) reduced modulo n, read by rows; T(0,0)=0 by convention. 13
0, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 2, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 3, 2, 3, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 4, 0, 6, 0, 4, 0, 1, 1, 0, 0, 3, 0, 0, 3, 0, 0, 1, 1, 0, 5, 0, 0, 2, 0, 0, 5, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 6, 4, 3, 0, 0, 0, 3, 4, 6, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
0,13
COMMENTS
Pascal's triangle read by rows, where row n is read mod n.
A number n is a prime if and only if (1+x)^n == 1+x^n (mod n), i.e., if and only if the n-th row is 1,0,0,...,0,1. This result underlies the proof of Agrawal, Kayal and Saxena that there is a polynomial-time algorithm for primality testing. - N. J. A. Sloane, Feb 20 2004
A020475(n) = number of zeros in n-th row, for n > 0. - Reinhard Zumkeller, Jan 01 2013
LINKS
M. Agrawal, N. Kayal & N. Saxena, PRIMES is in P, Annals of Maths., 160:2 (2004), pp. 781-793. [alternate link]
EXAMPLE
Row 4 = 1 mod 4, 4 mod 4, 6 mod 4, 4 mod 4, 1 mod 4 = 1, 0, 2, 0, 1.
Triangle begins:
0;
0,0;
1,0,1;
1,0,0,1;
1,0,2,0,1;
1,0,0,0,0,1;
1,0,3,2,3,0,1;
1,0,0,0,0,0,0,1;
1,0,4,0,6,0,4,0,1;
1,0,0,3,0,0,3,0,0,1;
1,0,5,0,0,2,0,0,5,0,1;
1,0,0,0,0,0,0,0,0,0,0,1;
1,0,6,4,3,0,0,0,3,4,6,0,1;
1,0,0,0,0,0,0,0,0,0,0,0,0,1;
MAPLE
f := n -> seriestolist( series( expand( (1+x)^n ) mod n, x, n+1)); # N. J. A. Sloane
MATHEMATICA
Flatten[Join[{0}, Table[Mod[Binomial[n, Range[0, n]], n], {n, 20}]]] (* Harvey P. Dale, Apr 29 2013 *)
PROG
(Haskell)
a053200 n k = a053200_tabl !! n !! k
a053200_row n = a053200_tabl !! n
a053200_tabl = [0] : zipWith (map . flip mod) [1..] (tail a007318_tabl)
-- Reinhard Zumkeller, Jul 10 2015, Jan 01 2013
(PARI) T(n, k)=if(n, binomial(n, k)%n, 0) \\ Charles R Greathouse IV, Feb 07 2017
CROSSREFS
Row sums give A053204. Cf. A053201, A053202, A053203, A007318 (Pascal's triangle).
Cf. also A092241.
Cf. A053214 (central terms, apart from initial 1).
Sequence in context: A025426 A269244 A204246 * A050870 A103306 A269249
KEYWORD
nonn,tabl,nice
AUTHOR
Asher Auel, Dec 12 1999
EXTENSIONS
Corrected by T. D. Noe, Feb 08 2008
Edited by N. J. A. Sloane, Aug 29 2008 at the suggestion of R. J. Mathar
STATUS
approved

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Last modified April 25 03:15 EDT 2024. Contains 371964 sequences. (Running on oeis4.)