131361

Appears in sequences

• a(n) = 2^n + n^2.at n=17A001580
• Leyland numbers: 3, together with numbers expressible as n^k + k^n nontrivially, i.e., n,k > 1 (to avoid n = (n-1)^1 + 1^(n-1)).at n=33A076980
• Numbers of the form p^2 + 2^p for p prime.at n=6A097058
• a(n) = n^d+d^n where d = A013632(n) is the distance to the next prime.at n=16A171240
• Numbers of the form x^y + y^x, 1 < x < y.at n=27A173054
• Numbers of the form a^b+b^a, a and b are primes.at n=11A173056
• a(n) = 324*n^2 - 564*n + 321 (n>=1).at n=20A304617
• Leyland numbers which are products of two distinct primes.at n=6A356423
• a(n) = Sum_{p|n, p prime} p^sopf(n/p).at n=33A369912
• Expansion of Sum_{p prime} p * x^p / (1 - p * x^p).at n=33A382513
• Numbers that can be written as s^x + t^y, with 1 < s < t and {s,t} = {x,y}; that is, are of the form s^s + t^t or s^t + t^s.at n=37A385232