19934

Appears in sequences

• a(n) = 5*a(n-2) - 2*a(n-4), with initial terms 0,1,2,4.at n=14A079162
• Numbers k such that 2^k + 13 is prime.at n=10A102634
• a(n) = 5*a(n-2) - 2*a(n-4), n >= 4.at n=13A109165
• a(1) = 1. If a(n) is composite, a(n+1) = 2*a(n)+1; otherwise, a(n+1) = 2*a(n).at n=14A125050
• Elements of A011185 that are also the sum of a pair of distinct elements of A011185.at n=17A133605
• a(n) = A000043(n) - 3.at n=22A139480
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, 0, 0), (-1, 1, 1), (0, -1, 0), (1, 0, 0), (1, 1, -1)}.at n=9A148736
• The number of 1 X n Haunted Mirror Maze puzzles with a unique solution ending with a mirror.at n=7A204091
• Numbers n such that sigma(Rev(phi(n))) = phi(Rev(sigma(n))), where sigma is the sum of divisors and phi the Euler totient function.at n=7A252255
• G.f.: Sum_{n=-oo..+oo} x^n * (1 - x^n)^(3*n).at n=44A268298