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A242350 Multiply a(n-1) by 2 and drop all 0's. 10
1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 124, 248, 496, 992, 1984, 3968, 7936, 15872, 31744, 63488, 126976, 253952, 5794, 11588, 23176, 46352, 9274, 18548, 3796, 7592, 15184, 3368, 6736, 13472, 26944, 53888, 17776, 35552, 7114, 14228, 28456, 56912, 113824 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
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
Zeroless analog of powers of 2. - N. J. A. Sloane, Jun 11 2014
LINKS
Index entries for linear recurrences with constant coefficients, 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).
EXAMPLE
Term after 512 is 124 because 512*2=1024, and 1024 becomes 124 if all 0's are taken out.
MATHEMATICA
NestList[FromDigits[Select[IntegerDigits[2 #], #!=0&]]&, 1, 50] (* Harvey P. Dale, Oct 22 2018 *)
PROG
(PARI) dropz(n)=d = digits(n); s = 0; for (i=1, #d, if (d[i], s = 10*s + d[i]); ); s;
lista(nn) = a = 1; for (i=1, nn, print1(a, ", "); a = dropz(2*a); ) \\ Michel Marcus, May 12 2014
CROSSREFS
Sequence in context: A072067 A072049 A281938 * A115213 A009714 A051535
KEYWORD
nonn,base
AUTHOR
J. Lowell, May 11 2014
EXTENSIONS
More terms from Michel Marcus, May 12 2014
STATUS
approved

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Last modified July 18 01:34 EDT 2024. Contains 374377 sequences. (Running on oeis4.)