77028

Appears in sequences

• Number of 3 X 3 integer matrices with elements in the range [ -n,n ] which represent a six-fold rotation. Also the sequence for the corresponding six-fold rotoinversions.at n=5A053174
• Triangular numbers for which the number of divisors is also a triangular number.at n=25A116541
• Numbers k such that 2*6^k + 1 is prime.at n=33A120023
• Cyclops triangular numbers.at n=17A160717
• a(n) = larger member of n-th pair of distinct, positive, triangular numbers whose sum and difference are also triangular numbers.at n=10A185128
• a(n) = n^2*(2*n^2 + (-1)^n).at n=14A275496
• Number of 4-cycles in the n-triangular honeycomb queen graph.at n=14A289705