26521
domain: N
Appears in sequences
- q-integers for q=-13.at n=4A015000
- Triangle of (Gaussian) q-binomial coefficients for q = -13.at n=16A015129
- Triangle of (Gaussian) q-binomial coefficients for q = -13.at n=19A015129
- Gaussian binomial coefficient [ n,4 ] for q = -13.at n=1A015303
- Cyclotomic polynomials at x=13.at n=10A019331
- Strong pseudoprimes to base 13.at n=13A020239
- Cyclotomic polynomials at x=-13.at n=5A020512
- a(n) = n^4 - n^3 + n^2 - n + 1.at n=13A060884
- Column k=4 sequence of array A103728.at n=8A103731
- Integers n such that 17+30*n are terms in A172456.at n=16A175103
- Volume of sphere (rounded down) with the diameter equal to n.at n=36A228272
- Expansion of f(-x) * psi(x^2) * phi(x^3) / f(-x^3)^3 in powers of x where phi(), psi(), f() are Ramanujan theta functions.at n=39A230256
- a(n) = 1 - sigma(n) + sigma(n)^2 - sigma(n)^3 + sigma(n)^4.at n=8A259410
- Expansion of Product_{k>=1} 1/(1 - x^k)^(k*(2*k^2+1)/3).at n=9A279761
- Indices of records in A307730.at n=41A348449
- a(n) = Sum_{j=1..n} Sum_{k=1..n} phi(n*j*k) / phi(n*k).at n=40A372669