%I A002270
%S A002270 4,6,22
%N A002270 Composite n such that n*sigma(n) == 2 (mod phi(n)).
%D A002270 M. V. Subbarao, On two congruences for primality. Pacific J. Math. 52 
               (1974), 261-268.
%D A002270 J. Roberts, Lure of the Integers, Math. Assoc. America, 1992, p. 147.
%Y A002270 Cf. A051948.
%Y A002270 Sequence in context: A019147 A026722 A151520 this_sequence A088228 A108636 
               A101143
%Y A002270 Adjacent sequences: A002267 A002268 A002269 this_sequence A002271 A002272 
               A002273
%K A002270 nonn,fini,full,bref
%O A002270 1,1
%A A002270 N. J. A. Sloane (njas(AT)research.att.com).
%E A002270 Definition corrected by Tanya Khovanova, Nov 05 2007