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%I #8 Jun 13 2022 16:47:15
%S 1,2,3,4,5,6,7,8,9,10,11,13,14,16,17,18,19,22,23,25,26,27,29,31,32,34,
%T 37,38,41,43,46,47,49,50,53,54,58,59,61,62,64,67,71,73,74,79,81,82,83,
%U 86,89,94,97,98,101,103,106,107,109,113,118,121,122,125,127,128,131,134,137,139,142,146,149,151,157,158
%N Numbers k such that A047994(k) = A344005(k).
%t f[p_, e_] := p^e - 1; uphi[n_] := Times @@ f @@@ FactorInteger[n]; uphi[1] = 1; q[n_] := Module[{m = 1, u = uphi[n]}, While[m <= u && ! Divisible[m*(m + 1), n], m++]; m == u]; Select[Range[160], q] (* _Amiram Eldar_, Jun 13 2022 *)
%o (PARI)
%o A047994(n) = { my(f=factor(n)~); prod(i=1, #f, (f[1, i]^f[2, i])-1); };
%o A344005(n) = for(m=1, oo, if((m*(m+1))%n==0, return(m))); \\ From A344005
%o A354924(n) = (A047994(n)==A344005(n));
%o isA354928(n) = A354924(n);
%Y Cf. A346608 (complement), A354924 (characteristic function).
%Y Cf. A047994, A344005.
%Y Positions of zeros in A346607.
%K nonn
%O 1,2
%A _Antti Karttunen_, Jun 13 2022
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