A068359 Binomial(2k,k) when the first digit of binomial(2k,k) is 1.

1, 12870, 184756, 10400600, 155117520, 137846528820, 126410606437752, 1946939425648112, 118264581564861424, 1832624140942590534, 112186277816662845432, 1746130564335626209832, 107507208733336176461620, 1678910486211891090247320, 103827421287553411369671120

Offset: 1

Author

Benoit Cloitre, Feb 28 2002

Keywords

• easy
• nonn
• base

Crossrefs

Intersection of A000984 and A131835.

Cf. A068358 (k values).

Programs

Mathematica

a={}; kmax=40; For[k=0, k<=kmax, k++, If[First[IntegerDigits[term = Binomial[2k, k]]]==1, AppendTo[a, term]]]; a (* Stefano Spezia, Sep 06 2022 *)

Extensions

a(1) = 1 inserted by Stefano Spezia, Sep 06 2022