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Numbers n such that gcd( binomial(2n,n), 3*5*7*11 ) = 1.
5

%I #15 Oct 01 2017 10:01:15

%S 0,1,3160

%N Numbers n such that gcd( binomial(2n,n), 3*5*7*11 ) = 1.

%C It is conjectured that there are no other terms.

%C There are no further terms below 10^10000.

%H R. D. Mauldin, S. M. Ulam, <a href="http://dx.doi.org/10.1016/0196-8858(87)90026-1">Mathematical problems and games</a>, Adv. Appl. Math. 8 (3) (1987) 281-344.

%H C. Pomerance, <a href="https://math.dartmouth.edu/~carlp/catalan5.pdf">Divisors of the middle binomial coefficient</a>, Amer. Math. Monthly, 112 (2015), 636-644.

%K nonn,bref

%O 1,3

%A _N. J. A. Sloane_, Jul 30 2009