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%I #7 Feb 11 2014 19:05:25
%S 1254,4180,10542,12798,45594,54834,217938,2305100,4926846,35645478,
%T 36227862,49934598,53384500,85355648,234600618,511921340,847743090,
%U 1581255708,1609288450,1630012240,4209017505,4445096658,9088300212,9828008364,13299474798,47009516442
%N Numbers n such that sigma(n) = phi(n) + phi(n-1) + phi(n-2) + phi(n-3).
%e sigma(1254) = 2880 = 360 + 1068 + 624 + 828 = phi(1254) + phi(1254-1) + phi(1254-2) + phi(1254-3), so 1254 is a term of the sequence.
%t Select[Range[4, 10^5], EulerPhi[ # ] + EulerPhi[ # - 1] + EulerPhi[ # - 2] + EulerPhi[ # - 3] == DivisorSigma[1, # ] &]
%K nonn
%O 1,1
%A _Joseph L. Pe_, Feb 19 2002
%E a(7)-a(26) from _Donovan Johnson_, Feb 08 2012
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