A207982 - OEIS

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A207982

Least m>1 such that all central binomial coefficients C(2k,k), k<=n, are pairwise not congruent mod m.

2, 3, 5, 11, 11, 11, 23, 23, 23, 31, 43, 43, 43, 43, 59, 59, 59, 59, 107, 149, 151, 151, 151, 151, 163, 163, 163, 163, 163, 163, 163, 163, 163, 277, 277, 277, 277, 401, 401, 457, 457, 457, 457, 457, 457, 457, 479, 479, 479, 479, 479, 479, 479, 479, 479, 479

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..5000

Z. W. Sun, A function taking only prime values, Number Theory list, Feb 21 2012

PROG

(PARI) m=2; for(n=1, 99, forstep(nn=n, 2, -1, for(k=1, nn-1, (binomial(nn*2, nn)-binomial(2*k, k))%m&next; m++; nn=n+1; next(2))); print1(m", "))

CROSSREFS

Sequence in context: A258975 A111214 A272197 * A259155 A354400 A210144

Adjacent sequences: A207979 A207980 A207981 * A207983 A207984 A207985

KEYWORD

nonn

AUTHOR

M. F. Hasler, Feb 22 2012

STATUS

approved