37446

Appears in sequences

• usigma(n) = 2n + d(n), where d(n) is the number of divisors of n.at n=20A063829
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, 0, 0), (1, -1, 1), (1, 1, -1), (1, 1, 1)}.at n=9A149445
• Number of triple-rises in all length n left factors of Dyck paths (triple-rise = three consecutive (1,1)-steps).at n=16A191787
• Upper Pythagorean twins.at n=23A228877
• Numbers k such that 7*R_k + 10^k - 6 is prime, where R_k = 11...11 is the repunit (A002275) of length k.at n=8A259121
• Differences of the increasing arithmetic progression a^2+a, b^2+b, c^2+c, where b = 5*a+2, c = 7*a+3 and a >= 0.at n=39A260955
• Numbers k such that s(k) = 2*k, where s(k) is the sum of divisors of k that have a square factor (A162296).at n=25A322609
• Numbers k such that p^2 divides k, where p = A006530(k), the largest prime factor of k, and sigma(k) does not have any prime factor larger than p.at n=38A336354
• a(n) = prime(n)^2 + prime(n+1).at n=43A352851
• Numbers k such that sigma(k) = psi(k) + tau(k).at n=42A387953