26934

Appears in sequences

• Binomial transform of A000029.at n=11A054192
• McKay-Thompson series of class 15C for Monster.at n=18A058510
• usigma(n) = 2n + d(n), where d(n) is the number of divisors of n.at n=17A063829
• McKay-Thompson series of class 15C for the Monster group with a(0) = 3.at n=18A153084
• E.g.f. equals the series reversion of x - x*arcsinh(x).at n=5A227459
• Expansion of f(-x^8)^2 / f(-x) in powers of x where f() is a Ramanujan theta function.at n=42A260164
• 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=33A260955
• Number of nX6 0..2 arrays with no element equal to more than one of its king-move neighbors and with new values introduced in order 0 sequentially upwards.at n=12A280857
• Numbers k such that k^2+1, (k+2)^2+1 and (k+6)^2+1 are prime.at n=41A302021
• 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=21A322609
• 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=30A336354
• Number of polygons formed by infinite lines when connecting all vertices and all points that divide the sides of an equilateral triangle into n equal parts.at n=9A344279
• Number of multisets whose right half (inclusive) sums to n.at n=28A360671
• Numbers k such that sigma(k) = psi(k) + tau(k).at n=37A387953