%I #17 Jan 25 2024 05:27:53
%S 3,6,10,12,14,15,22,24,26,30,34,42,44,46,62,69,74,82,94,106,114,118,
%T 122,134,135,146,166,194,198,202,206,214,262,282,302,314,334,346,366,
%U 382,386,446,454,466,474,502,514,526,542,554,614,622,662,694
%N Numbers k such that phi(k + 12) | sigma(k) + 12.
%H Harvey P. Dale, <a href="/A015875/b015875.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[700],Divisible[DivisorSigma[1,#]+12,EulerPhi[#+12]]&] (* _Harvey P. Dale_, Apr 14 2021 *)
%o (PARI) is(n)=!((sigma(n)+12)%eulerphi(n+12)) \\ _Charles R Greathouse IV_, Sep 25 2012
%Y Cf. A000010, A000203.
%K nonn
%O 1,1
%A _Robert G. Wilson v_
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