17970

Appears in sequences

• Numbers that define integer Heronian triangles [prime(a(n)), prime(a(n)+1), A068965(n)] with area A068966(n).at n=21A068964
• Numbers k such that sigma(k) - phi(k) is a 4th power.at n=22A115918
• Number of connected regular simple graphs on n vertices with girth exactly 4.at n=16A186744
• Right hand diagonal of triangle A199476.at n=12A199477
• a(n) = 4*n^3 - 18*n^2 + 27*n - 12.at n=17A271828
• Convolution of number of partitions into distinct parts and central binomial coefficients.at n=8A304823
• Sum of the second largest parts in the partitions of n into 6 parts.at n=40A308872
• Number of edges in a hexagon when n internal hexagons are drawn between the 6n points that divide each side into n+1 equal parts.at n=39A357198
• Rank of the partition of n formed by the terms of its binary expansion from largest to smallest.at n=35A380207