1,1

Let f(k) be the sequence of numbers that appear as binomial coefficients exactly k times:

f(1) = {2}.

f(2) = A137905.

f(3) = A000984 (central binomial coefficients) except for first 2 terms: {1,2}.

f(4) = this sequence.

f(5) appears to be empty.

f(6) = A098565.

f(7) appears to be empty.

f(8) begins with 3003.

Cf. A000984, A098565, A137905.

Sequence in context: A108614 A115708 A068992 this_sequence A062691 A129496 A075520

Adjacent sequences: A098561 A098562 A098563 this_sequence A098565 A098566 A098567

nonn

Paul D. Hanna (pauldhanna(AT)juno.com), Oct 27 2004