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A320263
Write n in binary, then modify each run of 0's and each run of 1's by prepending a 0. a(n) is the decimal equivalent of the result.
2
1, 4, 3, 8, 17, 12, 7, 16, 33, 68, 35, 24, 49, 28, 15, 32, 65, 132, 67, 136, 273, 140, 71, 48, 97, 196, 99, 56, 113, 60, 31, 64, 129, 260, 131, 264, 529, 268, 135, 272, 545, 1092, 547, 280, 561, 284, 143, 96, 193, 388, 195, 392, 785, 396, 199, 112, 225, 452, 227
OFFSET
1,2
COMMENTS
A variation of A175046. Indices of record values are given by A319423.
FORMULA
a(n) = A320262(n)/2.
EXAMPLE
6 in binary is 110. Modify each run by prepending a 0 to get 01100, which is 12 in decimal. So a(6) = 12.
PROG
(Python)
from re import split
def A320263(n):
return int(''.join('0'+d for d in split('(0+)|(1+)', bin(n)[2:]) if d != '' and d != None), 2)
KEYWORD
nonn,base
AUTHOR
Chai Wah Wu, Oct 08 2018
STATUS
approved