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A114645
The numbers 2^n-1 written in groups of three digits, with leading zeros omitted.
5
137, 153, 163, 127, 255, 511, 102, 320, 474, 95, 819, 116, 383, 327, 676, 553, 513, 107, 126, 214, 352, 428, 710, 485, 752, 97, 151, 419, 430, 383, 886, 71, 677, 721, 533, 554, 431, 671, 88, 631, 342, 177, 272, 684, 354, 555, 368, 709, 111, 73, 741, 823, 214, 748
OFFSET
1,1
REFERENCES
Heard over coffee at the Computers in Scientific Discovery meeting in Ghent, Feb 02 2006.
LINKS
EXAMPLE
1,3,7,15,31,63,...
MATHEMATICA
FromDigits[#] & /@ Partition[ Flatten[ IntegerDigits[ Table[ 2^n - 1, {n, 31}]]], 3] (* Robert G. Wilson v, Jun 23 2014 *)
PROG
(Python)
from itertools import count, islice
def bgen(): yield from (d for n in count(1) for d in str((1 << n)-1))
def agen(): g = bgen(); yield from (int("".join(t)) for t in zip(g, g, g))
print(list(islice(agen(), 54))) # Michael S. Branicky, Dec 25 2022
CROSSREFS
Sequence in context: A138329 A066477 A139647 * A057879 A179912 A108382
KEYWORD
nonn,base,dumb
AUTHOR
N. J. A. Sloane, Feb 18 2006
EXTENSIONS
More terms from Matthew Conroy, Mar 12 2006
STATUS
approved