OFFSET
1,1
COMMENTS
FORMULA
a(n) = A185024(n+1). - Elijah Beregovsky, May 14 2019
EXAMPLE
7 is a member because 7 = binomial(7, 1) = binomial(7, 6) and no other binomial coefficient equals 7. [clarified by Jonathan Sondow, Jan 12 2018]
PROG
(PARI) isok(n) = (sum(i=0, n, sum(j=0, i, binomial(i, j)==n)) == 2) \\ Michel Marcus, Jun 16 2013
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
David Wasserman, Feb 21 2008
STATUS
approved