

A015870


Numbers k such that phi(k + 4)  sigma(k) + 4.


0



6, 11, 12, 62, 65, 166, 251, 782, 2342, 6662, 25040, 83623931, 933180002, 943169410, 1840122962, 4294967291
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OFFSET

1,1


COMMENTS

There are no other terms < 4290000000.  Jud McCranie, Dec 26 1999


LINKS



EXAMPLE

phi(6+4)=4, which divides 16=sigma(6)+4, so 6 is a term of the sequence.


MATHEMATICA

Select[Range[100000],
Divisible[DivisorSigma[1, #] + 4, EulerPhi[# + 4]] &] (* David Nacin, Feb 28 2012 *)


PROG



CROSSREFS



KEYWORD

nonn,more


AUTHOR



EXTENSIONS



STATUS

approved



