Gozinta Chains
February 21, 2016
A gozinta chain for n is a sequence {1,a,b,...,n} where each element properly divides the next. There are eight gozinta chains for 12: {1,12} ,{1,2,12}, {1,2,4,12}, {1,2,6,12}, {1,3,12}, {1,3,6,12}, {1,4,12} and {1,6,12}. Let g(n) be the number of gozinta chains for n, so g(12)=8. g(48)=48 and g(120)=132.
Find the sum of the numbers n not exceeding 1016 for which g(n)=n.
Written by gamwe6 who lives and works in San Francisco building useful things. You should follow him on Twitter