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A115619
Sigma(A033631(n)) {sigma is the sum of divisors function A000203}.
2
1, 120, 546, 1680, 2880, 7812, 14520, 34200, 40320, 40320, 53760, 68796, 63360, 76608, 78624, 80640, 89280, 86400, 95040, 90720, 129600, 178560, 155496, 205920, 214272, 190080, 223200, 245520, 241920, 244800, 267840, 280800, 259200, 312480, 345600, 313560, 393120, 374976, 401760, 367200, 464256
OFFSET
1,2
PROG
(PARI) for(n=1, 1e6, if(sigma(eulerphi(n))==sigma(n), print1(sigma(n)", "))) \\ Charles R Greathouse IV, Feb 19 2013
CROSSREFS
Sequence in context: A221563 A336626 A241613 * A152622 A100145 A234437
KEYWORD
nonn
AUTHOR
Lekraj Beedassy, Jan 26 2006
STATUS
approved