277750

Appears in sequences

• Numbers k such that 1*k + 1, 3*k + 1, 9*k + 1, 27*k + 1, 81*k + 1 are all primes.at n=14A112042
• a(n) = 6^n - 3^n + 1.at n=7A155611
• Let (n)_p denote the exponent of prime p in the prime power factorization of n. Then a(n) is defined by the formulas a(1)=1; for n >= 2, (a(n))_2 = (n)_2, (a(n))_3 = (n)_3 and, for p >= 5, (a(n))_p = 1 + ((2n)/(p-1))_p if p-1|2*n, and (a(n))_p = 0 otherwise.at n=49A202318