37921

Appears in sequences

• Strong pseudoprimes to base 54.at n=19A020280
• Replace n with concatenation of its nontrivial odd divisors.at n=62A037285
• Replace 2n+1 with concatenation of its nontrivial divisors.at n=31A037288
• Smallest m such that the period of the continued fraction of sqrt(m) is A215485(n); records of A013646.at n=27A215508
• Centered 12-gonal numbers which are semiprimes, intersection of A003154 and A001358.at n=34A218172
• Composite numbers n such that the distinct digits in n and the distinct digits in the proper divisors of n are the same.at n=22A237713
• a(n) = 1 + a(n-1) + a(n-2) + a(n-3) if n>=4; a(1) = a(2) = a(3) = 1.at n=18A248098
• E.g.f. satisfies: A(x - Integral 2*A(x) dx) = x - Integral A(x) dx.at n=5A279845
• Numbers k such that the set of all the decimal digits of k is the same as the set of all the decimal digits of the proper divisors of k.at n=23A282755
• Triangle read by rows: T(n,w) is the number of n-step self avoiding walks on a 3D cubic lattice confined inside a tube of cross section 2w X 2w where the walk starts at the center of the tube's side.at n=25A337401
• Triangle read by rows: T(n,w) is the number of n-step self avoiding walks on a 3D cubic lattice confined between two infinite horizontal planes a distance 2w apart and an orthogonal plane on the y-z axes, where the walk starts at the middle point between the planes on the y-z plane.at n=25A338127