19036

Appears in sequences

• a(n) = sum of absolute-valued coefficients of (1+2*x-x^2)^n.at n=9A084776
• Numbers n such that 9*10^n + 7*R_n - 6 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=12A103105
• Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 01010-11111 pattern in any orientation.at n=15A147065