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A053200 Binomial coefficients C(n,k) reduced modulo n, read by rows ; T(0,0)=0 by convention . 10
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; 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 polynomial-time algorithm for primality testing. - N. J. A. Sloane (njas(AT)research.att.com), Feb 20, 2004

REFERENCES

M. Agrawal, N. Kayal and N. Saxena, PRIMES is in P, Ann. of Math. (2) 160 (2004), no. 2, 781-793.

LINKS

T. D. Noe, Rows n=0..100 of triangle, flattened

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)

CROSSREFS

Row sums give A053204. Cf. A053201, A053202, A053203, A007318 (Pascal's triangle)

Cf. also A092241.

Cf. A007318.

Sequence in context: A158924 A025426 A204246 * A050870 A103306 A163510

Adjacent sequences:  A053197 A053198 A053199 * A053201 A053202 A053203

KEYWORD

nonn,tabl,nice

AUTHOR

Asher Auel (asher.auel(AT)reed.edu) Dec 12, 1999

EXTENSIONS

Corrected by T. D. Noe, Feb 08 2008

Edited by N. J. A. Sloane (njas(AT)research.att.com), Aug 29 2008 at the suggestion of R. J. Mathar

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Last modified February 14 11:32 EST 2012. Contains 205623 sequences.