25121

Properties

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has period 73.at n=17A020412
• Denominators of continued fraction convergents to sqrt(390).at n=9A041741
• Group the natural numbers so that the n-th group contains n numbers whose sum as well as the group product +1 is prime. Sequence contains the primes arising as the sum of the terms of groups.at n=36A092946
• Primes p such that p^3 - 12 and p^3 + 12 are also primes.at n=29A153322
• Number of planar n X n X n binary triangular grids with mirror symmetry about one altitude with no more than 1 one in any 5 X 5 X 5 subtriangle.at n=18A153906
• Primes of the form 4*n^2 + 2*n -1.at n=38A155737
• Primes of the form p^2 +3p + 1, where p is also a prime.at n=16A165944
• a(n) = 840*n^2 - 23100*n + 86861.at n=3A216257
• Prime p such that p^5 + p^3 + p - 4 and p^5 + p^3 + p + 4 are primes.at n=24A243900
• Prime numbers p such that p^3 is an interprime = average of two successive primes.at n=35A248799
• Primes of form n^2 + 4096.at n=22A256836
• Numbers k that end with ( sum of digits of k )^2.at n=34A270343
• Numbers k such that (13*10^k + 107)/3 is prime.at n=18A294908
• Lengths of largest face diagonal in primitive Euler bricks or Pythagorean cuboids: possible values of max(d, e, f) for solutions to a^2 + b^2 = d^2, a^2 + c^2 = e^2, b^2 + c^2 = f^2 in coprime positive integers a, b, c, d, e, f.at n=28A306120
• Expansion of 1 / Sum_{k>=0} (-x)^(k*(3*k - 1)/2).at n=41A308806
• Primes which, when added to their reversals, produce palindromic primes.at n=38A342681
• Primes that can be constructed by concatenating two squares >= 4.at n=22A345314
• Primes such that x^16 = 2 has a solution in Z/pZ, but x^32 = 2 does not.at n=8A373468
• Triangle read by rows: T(n, k) = n! * 4^k * hypergeom([-k], [-n], -1/4).at n=19A375612
• Primes having only {1, 2, 5} as digits.at n=30A385773