%I A117287
%S A117287 1,2,3,5,7,11,13,15,17,19,23,29,31,34,37,41,43,47,49,53,59,61,67,71,73,
%T A117287 79,83,89,97,101,103,107,109,113,127,131,137,139,149,151,157,159,163,
%U A117287 167,173,175,179,181,189,191,193,196,197,199,208,211,223,227,229,233
%N A117287 Numbers n for which the cototient n-phi(n) is a heptagonal number.
%e A117287 49 is in the sequence because 49-phi(49)=7, which is a heptagonal number.
%Y A117287 Cf. A000566.
%Y A117287 Sequence in context: A102553 A069161 A003277 this_sequence A121615 A097605 
               A143578
%Y A117287 Adjacent sequences: A117284 A117285 A117286 this_sequence A117288 A117289 
               A117290
%K A117287 nonn
%O A117287 0,2
%A A117287 Luc Stevens (lms022(AT)yahoo.com), Apr 23 2006