28780

Appears in sequences

• Number of lines through exactly 3 points of an n X n grid of points.at n=32A018810
• Number of partitions of n^3 into distinct cubes.at n=43A030272
• Numbers k whose decimal representation, read as a base-18 value and divided by k, yields an integer.at n=31A032567
• Interprimes which are of the form s*prime, s=20.at n=26A075295
• Numbers whose natural logarithm, in base 10, starts with 10 distinct digits.at n=9A113509
• Numbers k such that k and k^2 use only the digits 0, 2, 4, 7 and 8.at n=41A136906
• Vinogradov's constants arising in enumeration of solutions to Waring's problem in the evil numbers (A001969).at n=37A206375
• a(n) = Sum_{i=0..n} digsum_8(i)^4, where digsum_8(i) = A053829(i).at n=23A231683
• a(n) = Sum_{i=0..n} digsum_9(i)^4, where digsum_9(i) = A053830(i).at n=23A231687
• Numbers k such that sigma(k) = sigma(k - d(k)).at n=29A277273
• Numbers whose sum of divisors is equal to the product of the number of divisors of their k first powers, for some k.at n=37A283758
• Expansion of (1/(1 - x))*Product_{k>=1} (1 - x^(3*k))/(1 - x^k).at n=38A304630
• Place n equally spaced points on the circumference of a circle of radius r and then connect each pair of points with straight lines whose intersections create A007569(n) - n additional points. Draw a circle of radius r around each of the A007569(n) points. The sequence gives the total number of regions formed from all circle intersections.at n=9A374826