144841

Appears in sequences

• Strong pseudoprimes to base 24.at n=29A020250
• Strong pseudoprimes to base 90.at n=31A020316
• a(n) = diagonal sum of left justified array T given by A027113.at n=31A027131
• 7-gonal numbers which are sum of 2 consecutive 7-gonal numbers.at n=1A133324
• Expansion of (1+13*x+32*x^2+13*x^3+x^4)/(1-x)^5.at n=15A160765
• Heptagonal numbers (A000566) that are semiprimes (A001358).at n=33A259676
• On a spirally numbered square grid, with labels starting at 1, this is the number of steps that a (1,n) leaper makes before getting trapped, or -1 if it never gets trapped.at n=10A323469
• Triangle read by rows: T(m,n) (1 <= n < m) is the number of moves of an (m,n)-leaper (a generalization of a chess knight) until it can no longer move, starting on a board with squares spirally numbered from 1. Each move is to the lowest-numbered unvisited square. T(m,n) = -1 if the path never terminates.at n=45A323749