221815

Appears in sequences

• Dodecahedral numbers: a(n) = n*(3*n - 1)*(3*n - 2)/2.at n=37A006566
• Odd tetrahedral numbers: a(n) = (4*n+1)*(4*n+2)*(4*n+3)/6.at n=27A015219
• Values of C(n,3) which can be written as C(x,3) + C(y,3).at n=5A034404
• Number of (3,n)-partitions of a chain of length n^2.at n=11A055658
• Squarefree tetrahedral numbers.at n=31A070755
• Numbers n such that n, n+1, and the sum of those two numbers each have 4 or more distinct prime factors.at n=29A168630
• Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-2) + 2*n - 1, where a(0) = 1, a(1) = 2, b(0) = 3.at n=21A294540
• Tetrahedral numbers that are not divisible by any smaller tetrahedral number except 1.at n=28A318701
• a(n) = A000292(6*n + 1) where A000292 are the tetrahedral numbers.at n=18A349682
• Tetrahedral (or triangular pyramidal) numbers which are products of four distinct primes.at n=13A353027