2049300

Appears in sequences

• Triangular numbers which are 10-almost primes.at n=19A101744
• Number of partitions of {1...n} containing 4 pairs of consecutive integers, where each pair is counted within a block and a string of more than 2 consecutive integers are counted two at a time.at n=8A105481
• Let T(n) = n(n+1)/2 be the n-th triangular number (A000217); a(n) = T(8T(n)).at n=22A185096
• Triangular numbers that are the product of 4 distinct triangular numbers greater than 1.at n=12A226501
• Triangular numbers divisible by the square of the sum of their digits.at n=24A243008
• Triangular numbers that are the product of a triangular number and a square number (both greater than 1).at n=23A253650
• Triangular numbers with tetrahedral indices: a(n) = (1/72) * (n*(n+1)*(n+2)*(n+3)*(n^2+2)).at n=22A373733