23685

Appears in sequences

• Binary XOR of (3^k - 1)/2 as k varies from 1 to n.at n=9A199396
• Numbers k such that (19*10^k + 161)/9 is prime.at n=23A275323
• a(n) is the smallest positive integer which can be represented as the sum of distinct nonzero icosahedral numbers in exactly n ways, or -1 if no such integer exists.at n=17A360215