%I M3373 #17 Apr 15 2020 16:37:15
%S 1,4,10,12,22,26,30,46,54,62,66,78,94,110,126,134,138,158,162,186,190,
%T 222,254,270,278,282,318,326,330,374,378,382,402,446,474,510,542,558,
%U 566,570,638,654,662,666,750,758,762,766,806,810,834,894,950,954,978
%N A grasshopper sequence: closed under n -> 2n+2 and 6n+6.
%D C. Pickover, Computers and the Imagination, St. Martin's Press, NY, 1991, p. 353.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H Charles R Greathouse IV, <a href="/A007319/b007319.txt">Table of n, a(n) for n = 1..10000</a>
%H R. G. Wilson, V, <a href="/A007319/a007319.pdf">Letter to N. J. A. Sloane, Aug. 1992</a>
%t Take[ Sort[ Flatten[ NestList[{2#+2, 6#+6} &, 1, 8]]], 55] (* Wouter L.J. Meeussen Mar 06 2005 *)
%o (PARI) list(lim)=my(v=List([1]),x=1,X=4,y=1,Y=12,m); lim\=1; while((m=min(X,Y))<=lim, listput(v,m); if(m==X, X=v[x++]*2+2); if(m==Y, Y=v[y++]*6+6)); Vec(v) \\ _Charles R Greathouse IV_, Apr 15 2020
%Y Cf. A060031.
%K nonn,easy
%O 1,2
%A _N. J. A. Sloane_, _Mira Bernstein_
%E Corrected and extended by Larry Reeves (larryr(AT)acm.org), Apr 20 2001