340682

Appears in sequences

• Numbers k such that 27*2^k-1 is prime.at n=53A050539
• Number of truth tables of bracketed formulas (case 1).at n=9A218182
• a(1) = 0, a(2) = 1, and for n > 2, a(n) = 2*a(A252463(n)) + [n == 1 (mod 4)].at n=66A292385