%I #23 Sep 12 2017 02:50:54
%S 11,76,38,19,132,66,33,230,115,804,402,201,1406,703,4920,2460,1230,
%T 615,4304,2152,1076,538,269,1882,941,6586,3293,23050,11525,80674,
%U 40337,282358,141179,988252,494126,247063,1729440,864720,432360,216180,108090,54045,378314,189157,1324098
%N 7*x  1 Collatztype sequence starting with a(0) = 11.
%F a(0) = 11; a(n) = 7*a(n  1)  1 if a(n  1) is odd, a(n) = a(n  1)/2 if a(n  1) is even.
%e 11 is odd, so it's followed by 7*11  1 = 76.
%e 76 is even, so it's followed by 76/2 = 38.
%t NestList[If[OddQ[#], 7#  1, #/2] &, 11, 50]
%Y Cf. A063871.
%K nonn,easy
%O 0,1
%A _Alonso del Arte_, Sep 01 2017
