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%I #5 Jun 04 2021 04:44:19
%S 12,14,15,20,22,30,33,35,38,42,44,45,46,48,51,52,54,56,62,63,65,69,70,
%T 72,76,77,80,84,85,86,87,90,91,94,95,99,102,104,108,110,112,114,115,
%U 116,117,118,119,123,130,133,134,135,140,141,142,143,145,148,152,154,158,159,161,165,166,170,172,174,175,177,180
%N Numbers k, not a power of prime, such that for all their proper divisors d A011772(d) < A011772(k).
%o (PARI)
%o A011772(n) = { if(n==1, return(1)); my(f=factor(if(n%2, n, 2*n)), step=vecmax(vector(#f~, i, f[i, 1]^f[i, 2]))); forstep(m=step, 2*n, step, if(m*(m-1)/2%n==0, return(m-1)); if(m*(m+1)/2%n==0, return(m))); }; \\ From A011772
%o A344880(n) = { my(x=A011772(n)); fordiv(n,d,if(A011772(d)==x, return(d==n))); };
%o isA344883(n) = ((n>1)&&!isprimepower(n)&&(1==A344880(n)));
%Y Cf. A011772, A344880.
%Y Setwise difference A344881 \ A000961.
%K nonn
%O 1,1
%A _Antti Karttunen_, Jun 01 2021