153515

Appears in sequences

• a(n) = number of primes p, p <= 2^n, where 2^n + p is prime.at n=25A175147
• Coefficients of powers of x^2 of polynomials, called h(2,n,x^2), appearing in a conjecture on alternating sums of fifth powers of odd-indexed Chebyshev S polynomials stated in A220671.at n=39A220672