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%I #12 Jul 08 2020 17:40:08
%S 2,2,2,2,3,2,2,3,2,3,3,2,4,5,2,3,3,4,3,4,3,4,5,3,3,3,3,2,3,3,3,6,3,2,
%T 3,2,3,3,3,3,4,2,3,3,7,3,4,3,4,5,4,3,4,2,2,3,3,3,4,3,3,3,3,4,3,2,3,6,
%U 2,3,3
%N Number of ways n-th repdigit number, A010785(n), can be expressed as a polygonal number.
%H M. Keith, <a href="http://www.cs.uwaterloo.ca/journals/JIS/keith.html">On Repdigit Polygonal Numbers</a>, J. Integer Sequences, Vol. 1, 1998, #6.
%e 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.
%K nonn,base
%O 2,1
%A Mike Keith (domnei(AT)aol.com)
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