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Numbers k such that phi(k + 8) | sigma(k).
1

%I #24 Sep 03 2022 21:19:36

%S 6,7,10,30,41,46,54,55,62,66,70,78,108,114,118,132,135,138,168,174,

%T 186,188,190,195,220,246,286,297,318,354,357,378,382,391,434,438,460,

%U 474,510,534,553,606,618,646,654,667,702,748,754,780,786,834,836,852

%N Numbers k such that phi(k + 8) | sigma(k).

%H Vincenzo Librandi, <a href="/A015825/b015825.txt">Table of n, a(n) for n = 1..2000</a>

%t Select[Range[1000], Divisible[DivisorSigma[1, #], EulerPhi[8 + #]] &] (* _David Nacin_, Mar 01 2012 *)

%o (PARI) is(n)=sigma(n)%(eulerphi(n)+8)==0 \\ _Charles R Greathouse IV_, Sep 25 2012

%Y Cf. A000010 (phi), A000203 (sigma).

%K nonn

%O 1,1

%A _Robert G. Wilson v_