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A063710 Numbers k such that e(k) = s(k), where e(k) = eulerphi(sigma(k)+k) and s(n) = sigma(k-eulerphi(k)). 1

%I

%S 10,22,38,58,82,182,228,244,308,346,404,446,514,524,644,922,1020,1214,

%T 1484,1522,1538,1582,2104,2408,5600,5924,7596,8420,13352,13378,13738,

%U 14686,15012,20128,21272,27084,27580,29312,37158,43946,47284,47468

%N Numbers k such that e(k) = s(k), where e(k) = eulerphi(sigma(k)+k) and s(n) = sigma(k-eulerphi(k)).

%H Harry J. Smith, <a href="/A063710/b063710.txt">Table of n, a(n) for n = 1..350</a>

%o (PARI) s(n) = sigma(n-eulerphi(n)); e(n) = eulerphi(sigma(n)+n); j = []; for(n = 1,10^5, if(e(n) == s(n),j = concat(j,n))); j

%o (PARI) { n=0; for (x=2, 10^9, if (eulerphi(sigma(x) + x) == sigma(x - eulerphi(x)), write("b063710.txt", n++, " ", x); if (n==350, break)) ) } \\ _Harry J. Smith_, Aug 28 2009

%K easy,nonn

%O 1,1

%A _Jason Earls_, Aug 23 2001

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Last modified May 11 13:41 EDT 2021. Contains 343791 sequences. (Running on oeis4.)