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%I #32 Jun 29 2020 02:26:38
%S 1,2,4,8,16,32,64,128,256,512,124,248,496,992,1984,3968,7936,15872,
%T 31744,63488,126976,253952,5794,11588,23176,46352,9274,18548,3796,
%U 7592,15184,3368,6736,13472,26944,53888,17776,35552,7114,14228,28456,56912,113824
%N Multiply a(n-1) by 2 and drop all 0's.
%C Sequence enters a loop having period 36 at index 491: a(491) = a(527) = 366784, min and max being 28714 and 11772544. Starting with 3 instead of 1 gives another cycle. - _Tom Edgar_ and _Michel Marcus_, May 13 2014
%C Zeroless analog of powers of 2. - _N. J. A. Sloane_, Jun 11 2014
%H Michel Marcus, <a href="/A242350/b242350.txt">Table of n, a(n) for n = 1..600</a>
%H <a href="/index/Rec#order_36">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1).
%e Term after 512 is 124 because 512*2=1024, and 1024 becomes 124 if all 0's are taken out.
%t NestList[FromDigits[Select[IntegerDigits[2 #],#!=0&]]&,1,50] (* _Harvey P. Dale_, Oct 22 2018 *)
%o (PARI) dropz(n)=d = digits(n); s = 0; for (i=1, #d, if (d[i], s = 10*s + d[i]);); s;
%o lista(nn) = a = 1; for (i=1, nn, print1(a, ", "); a = dropz(2*a);) \\ _Michel Marcus_, May 12 2014
%Y Cf. A052382, A004719, A243063, A243657, A243658.
%K nonn,base
%O 1,2
%A _J. Lowell_, May 11 2014
%E More terms from _Michel Marcus_, May 12 2014
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