Numbers k such that the odd parts of sigma(k) and A064989(k) are equal, where A064989 shifts the prime factorization one step towards lower primes, and sigma is the sum of divisors function.
A374463
Numbers k such that the odd parts of sigma(k) and A064989(k) are equal, where A064989 shifts the prime factorization one step towards lower primes, and sigma is the sum of divisors function.
Terms
- a(0) =1a(1) =3a(2) =5a(3) =15a(4) =189a(5) =945a(6) =2125a(7) =6375a(8) =9261a(9) =42550a(10) =46305a(11) =127650a(12) =401625a(13) =936100a(14) =1191400a(15) =2808300a(16) =3574200a(17) =8041950a(18) =19679625a(19) =22469750a(20) =58378600a(21) =58506250a(22) =67409250a(23) =175135800a(24) =175518750a(25) =176922900a(26) =394055550a(27) =494334500
External references
- oeis: A374463