77180

Appears in sequences

• Third differences of Catalan numbers A000108.at n=9A033434
• a(n) = S1(n, 6), where S1(n, t) = Sum_{k=0..n} (k^t * Sum_{j=0..k} binomial(n,j)).at n=4A089663
• Both k and the reverse of k are pentagonal numbers (A000326).at n=11A115657