39340

Appears in sequences

• Number of n-step walks on a square lattice starting from the origin but not returning to it at any stage.at n=8A063887
• Sort the digits of these triangular numbers into descending order and drop zeros to get primes.at n=34A082923
• Numbers of the form prime(n) + prime(n+1) - 2 that are also triangular numbers, T(k) = k(k+1)/2.at n=26A110891
• The consecutive squares of numbers multiplied by their next consecutive integer.at n=25A193608
• Sequence of distinct least positive triangular numbers such that the arithmetic mean of the first n terms is also a triangular number. Initial term is 1.at n=10A236416
• a(n) = n*(n^2 - 3*n + 4).at n=35A242659
• Irregular triangle read by row: T(n,k), n>=1, k>=1, in which column k lists the numbers of A000716 multiplied by A000330(k), and the first element of column k is in row A000217(k).at n=41A252117
• Numbers k such that the symmetric representation of sigma(k) has only two parts and they meet at the center of the Dyck path.at n=15A262259
• a(n), n>1, is the smallest number k whose symmetric representation of sigma(k) has two parts and has a larger number of legs in its two parts than a(n-1); a(1)=3.at n=36A279105
• Triangular numbers that in base 2 have the same number of 0's and 1's.at n=22A345348
• The numbers appearing in the first layer of the number stack in A370193.at n=17A374496
• a(n) = A326128(n) * A389077(n).at n=71A388978