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A101440 Replace each digit of n with 1 followed by n 0's: 0 -> 1, 1 -> 10, 2 -> 100, ..., 9 -> 1000000000, 10 -> 101, 11 -> 1010, 12 -> 10100, etc. Expanded number is then converted from binary to decimal: 0 -> 1 -> 1, 1 -> 10 -> 2, 2 -> 100 -> 4, 9 -> 1000000000 -> 512, 10 -> 101 -> 5, etc. 0

%I

%S 1,2,4,8,16,32,64,128,256,512,5,10,20,40,80,160,320,640,1280,2560,9,

%T 18,36,72,144,288,576,1152,2304,4608,17,34,68,136,272,544,1088,2176,

%U 4352,8704,33,66,132,264,528,1056,2112,4224,8448,16896,65,130,260,520,1040

%N Replace each digit of n with 1 followed by n 0's: 0 -> 1, 1 -> 10, 2 -> 100, ..., 9 -> 1000000000, 10 -> 101, 11 -> 1010, 12 -> 10100, etc. Expanded number is then converted from binary to decimal: 0 -> 1 -> 1, 1 -> 10 -> 2, 2 -> 100 -> 4, 9 -> 1000000000 -> 512, 10 -> 101 -> 5, etc.

%e a(123) = 328 : 123 -> 101001000 -> 328

%K base,easy,nonn

%O 0,2

%A Felix Tubiana (fat2(AT)columbia.edu), Jan 18 2005

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Last modified July 29 11:51 EDT 2021. Contains 346346 sequences. (Running on oeis4.)