Numbers k such that sigma(phi(k)) = sigma(k) where sigma is the sum of divisors function A000203 and phi is the Euler totient function A000010.

A033631

Numbers k such that sigma(phi(k)) = sigma(k) where sigma is the sum of divisors function A000203 and phi is the Euler totient function A000010.

Terms

    a(0) =1a(1) =87a(2) =362a(3) =1257a(4) =1798a(5) =5002a(6) =9374a(7) =21982a(8) =22436a(9) =25978a(10) =35306a(11) =38372a(12) =41559a(13) =50398a(14) =51706a(15) =53098a(16) =53314a(17) =56679a(18) =65307a(19) =68037a(20) =89067a(21) =108946a(22) =116619a(23) =124677a(24) =131882a(25) =136551a(26) =136762a(27) =138975a(28) =144014a(29) =160629

External references