51785

Appears in sequences

• Replace 2n+1 with concatenation of its divisors >1.at n=42A037287
• a(n) = Sum_{k <= n/2 } k*binomial(n-2k, 3k+1).at n=21A137360
• Number of obtuse triangles, distinct up to congruence, on an n X n grid (or geoboard).at n=25A190022
• G.f.: 1/G(0) where G(k) = 1 + (-q)^(k+1) / (1 - (-q)^(k+1)/G(k+1) ).at n=63A227310
• Expansion of (Product_{k>0} (1 - x^k) / (1 - x^(5*k)))^5 in powers of x.at n=38A285932