2,1

M. Keith, On Repdigit Polygonal Numbers, J. Integer Sequences, Vol. 1, 1998, #6.

The n-th k-sided polygonal number is P(n,k)=n((k-2)n+4-k)/2 (k >= 2, n >= 1). For each repdigit number R>=2, sequence gives number of (n,k) such that P(n,k)=R.

Sequence in context: A074592 A089993 A047931 this_sequence A061357 A138139 A127992

Adjacent sequences: A033615 A033616 A033617 this_sequence A033619 A033620 A033621

nonn

Mike Keith (domnei(AT)aol.com)