128881

Appears in sequences

• Expansion of tan(tanh(x)/cos(x)).at n=4A009723
• a(n) = (9*n + 8)^2.at n=39A017258
• a(n) = (10*n + 9)^2.at n=35A017378
• a(n) = (11*n + 7)^2.at n=32A017474
• a(n) = (12*n + 11)^2.at n=29A017654
• a(n) = prime^2 and digits of prime do not appear in a(n).at n=17A030088
• Prime powers p^w (w >= 2) such that p^w-2 is prime.at n=38A053704
• Squares composed of digits {1,2,8}.at n=5A053887
• Numbers k such that sigma(k)*phi(k) is squarefree.at n=30A065299
• Composite numbers k such that the sum of the divisors of k^2 is a prime.at n=31A065405
• Squares that are the sum of 3 consecutive primes.at n=13A080665
• Squares of primes of the form 4*k+3.at n=36A087691
• a(n) = A045873(n)^2.at n=8A094423
• Squares for which the sum of the digits is a triangular number.at n=35A118488
• Numbers k of the form q^2, q = prime, such that k-2 is a prime.at n=28A146981
• Lucky numbers that are prime powers.at n=32A225322
• Squares whose digits are powers of 2.at n=15A272884
• Compact numbers: numbers that can be expressed more compactly using their prime factorization than their decimal expansion.at n=30A279070
• Totient highly abundant numbers that are composite.at n=14A286322
• Breadth-first reading of the subtree rooted at 7 of the tree where each parent node is the arithmetic derivative (A003415) of all its children.at n=60A327977