42253

Appears in sequences

• Weak preference orderings of n alternatives, i.e., orderings that have indifference between at least two alternatives.at n=7A019472
• Numbers k such that phi(sigma(phi(k))) = sigma(k).at n=10A066462
• Given n points in the complex plane, let M(n) the number of distinct Moebius transformations that take 3 distinct points to 3 distinct points. Note that the triples may have some or all of the points in common.at n=6A158121
• Numerator in the coefficient of x^n in exp( Sum_{m>=1} x^m/(m*2^(m^2)) ).at n=5A174490
• a(n) is the smallest number such that there are exactly n numbers k (including a(n) itself) such that U(k) is isomorphic to U(a(n)) (or 0 if no such number exists). Here U(k) is the multiplicative group of integers modulo k.at n=46A303712
• Expansion of g.f. A(x) satisfying A(x) = A(x^3) / A(x^2 - x^3 - x^4).at n=22A372533