130813

Appears in sequences

• a(n) = (nextprime(4^n) - nextprime(2^n))/2.at n=9A037131
• Binomial transform of 0, 1, 1, 7, 7, 31, 31, ..., zero followed by duplicated A083420.at n=11A140420
• a(n) = (1/4)*(9^n - 2*4^n + 3), n > 0; a(0) = 0.at n=6A386359