cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A063794 Numbers k such that usigma(k) = k + phi(k).

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%I A063794 #20 Jul 17 2023 06:05:51
%S A063794 2,28,1368,1700,342000,2061000,2120832,65834560,89082000
%N A063794 Numbers k such that usigma(k) = k + phi(k).
%C A063794 No other terms < 2700000000. - _Jud McCranie_, Nov 04 2001
%o A063794 (PARI) us(n) = sumdiv(n,d, if(gcd(d,n/d)==1,d));
%o A063794 for(n=1,10^8, if(us(n)==n+eulerphi(n),print1(n, ", ")))
%Y A063794 Cf. A000010, A034448, A121048.
%K A063794 nonn,more
%O A063794 1,1
%A A063794 _Jason Earls_, Aug 18 2001
%E A063794 More terms from _Jud McCranie_, Nov 04 2001
%E A063794 Offset corrected by _Mohammed Yaseen_, Jul 17 2023