OFFSET
1,2
LINKS
Paolo P. Lava and T. D. Noe, Table of n, a(n) for n = 1..1000 (first 270 terms from Paolo P. Lava)
EXAMPLE
29337 is in the sequence since:
sigma(29337)=49152 -> phi(49152)=16384 -> tau(16384)=15.
tau(29337)=16 -> phi(16)=8 -> sigma(8)=15.
MAPLE
MATHEMATICA
Select[Range[36099], DivisorSigma[1, EulerPhi[DivisorSigma[0, #]]] == DivisorSigma[0, EulerPhi[DivisorSigma[1, #]]] &] (* T. D. Noe, May 28 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Paolo P. Lava, May 27 2013
STATUS
approved