Numbers n such that phi(phi(n)) = phi(sigma(n)) where phi is Euler's totient and sigma is the multiplicative sum-of-divisors function.

A065555

Numbers n such that phi(phi(n)) = phi(sigma(n)) where phi is Euler's totient and sigma is the multiplicative sum-of-divisors function.

Terms

    a(0) =1a(1) =5a(2) =11a(3) =71a(4) =145a(5) =319a(6) =323a(7) =377a(8) =779a(9) =865a(10) =911a(11) =1007a(12) =1073a(13) =1167a(14) =1195a(15) =1343a(16) =1441a(17) =1585a(18) =1609a(19) =1691a(20) =1903a(21) =2117a(22) =2147a(23) =2249a(24) =2591a(25) =2629a(26) =2723a(27) =2987a(28) =3013a(29) =3107

External references