89973

Appears in sequences

• Numbers k that divide Sum_{i=1..k} phi(i)^2, where phi(i) = totient function A000010.at n=11A144857
• Integer lengths of log(2)-primes: numbers n such that the concatenation of the first n decimal digits of log(2) is prime.at n=5A228226
• Decimal representation of the x-axis, from the origin to the right edge, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 805", based on the 5-celled von Neumann neighborhood.at n=17A284140
• The number of non-equivalent distinguishing coloring partitions of the path on n vertices (n>=1) with exactly k parts (k>=1). Regular triangle read by rows: the rows are indexed by n, the number of vertices of the path, and the columns are indexed by k, the number of parts.at n=60A309748
• a(n) = Sum_{k=1..n} k^2*tau(k), where tau is A000005.at n=38A319085