128125

Appears in sequences

• Numbers k such that k | 4^k + 1.at n=18A015950
• Numbers k that divide 4^k + 1, k not a power of 5.at n=10A015974
• Numbers k that divide 8^k + 2^k.at n=39A045581
• Numbers k such that k^2 is composed of three 1-digit-overlapping subsquares.at n=21A048426
• Numbers j that are the hypotenuse of exactly 16 distinct integer-sided right triangles, i.e., j^2 can be written as a sum of two squares in 16 ways.at n=7A097238
• Solutions of the equation n" - n' - n = 0, where n' and n" are the first and second arithmetic derivatives (see A003415).at n=7A188145
• Numbers n for which n=(n'' mod n'), where n' and n'' are the first and second arithmetic derivative of n.at n=25A213241
• Value of y for solution of 5^n = x^2 + y^2 with closest x and y (n >= 0, 0 <= x < y).at n=15A236572
• a(n) = 5^n*(n+1)*(4*n^2+14*n+3)/3.at n=4A361610
• Numbers c such that a + b + c = d are abcd quadruples in the "abcd-conjecture" with a < b < c < d, all |a|, b, c, d are pairwise coprime, the quality q of the quadruple has q > 1, term a = +/- 1 = A376149(n) and term b = A376144(n) (with repetitions and sorted by c then b).at n=25A376143