Numbers k such that tau(k) = 2*tau(k-1) and sigma(k) = sigma(k-1), where tau(k) and sigma(k) are respectively the number and sum functions of the divisors of k.

A347603

Numbers k such that tau(k) = 2*tau(k-1) and sigma(k) = sigma(k-1), where tau(k) and sigma(k) are respectively the number and sum functions of the divisors of k.

Terms

    a(0) =4365a(1) =74919a(2) =79827a(3) =111507a(4) =347739a(5) =445875a(6) =739557a(7) =2168907a(8) =4481986a(9) =7263945a(10) =7845387a(11) =9309465a(12) =10838247a(13) =12290055a(14) =12673095a(15) =18151479a(16) =22083215a(17) =25645707a(18) =39175955a(19) =62634519a(20) =69076995a(21) =72794967a(22) =80889207a(23) =81166839a(24) =87215967a(25) =94682133a(26) =107522943a(27) =110768835a(28) =119192283

External references