1185030

Appears in sequences

• a(n) = n*(n^2 - 1)*(n + 2)*(n^2 + 4*n + 6)/72.at n=20A054563
• Triangular numbers which are 9-almost primes.at n=24A076583
• Smallest triangular number divisible by exactly n triangular numbers.at n=22A076983
• a(1) = 1; for n > 1, a(n) = smallest triangular number which is n times another triangular number > 1, or -1 if no such number exists.at n=53A077672
• Triangular numbers that set a new record for number of triangular divisors.at n=13A084260
• Sum of all parts of all partitions of n minus the number of partitions of n.at n=38A182724
• Triangular numbers that are the product of 4 distinct triangular numbers greater than 1.at n=7A226501
• Triangular numbers that can be represented as a sum of two distinct triangular numbers, and as a product of two triangular numbers greater than 1.at n=29A295768
• Triangular numbers that can be represented as a product of two triangular numbers greater than 1, and as a product of three triangular numbers greater than 1.at n=18A295769
• Triangular numbers that can be represented as a product of two triangular numbers greater than 1, as a product of three triangular numbers greater than 1, and as a product of four triangular numbers greater than 1.at n=6A296097
• a(n) is the smallest hexagonal number for which the symmetric representation of sigma(n) has width 2*n, n >= 0, at the diagonal.at n=9A350712
• Hexagonal numbers that are products of smaller hexagonal numbers.at n=11A374373