42005

Appears in sequences

• Sum of composite numbers up to n is palindromic.at n=13A057959
• Numbers k such that (94*10^k + 11)/3 is prime.at n=21A280019
• Solution of the complementary equation a(n) = a(n-1) + a(n-3) + a(n-4) + b(n-2), where a(0) = 1, a(1) = 2, a(2) = 3, a(3) = 4, b(0) = 5, b(1) = 6, b(2) = 7, b(3) = 8, and (a(n)) and (b(n)) are increasing complementary sequences.at n=20A295756