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A057613
Numbers that are both lucky numbers (A000959) and of form 2^k-1 (A000225).
0
1, 3, 7, 15, 31, 63, 127, 511, 1023, 4095, 8191, 131071, 524287, 2097151, 4194303, 8388607, 33554431, 67108863, 8589934591
OFFSET
1,2
COMMENTS
a(20) >= 17179869183 = 2^34 - 1, if it exists. - Kevin P. Thompson, Nov 24 2021
EXAMPLE
a(7) = 127 since A000959(27) = A000225(7) = 127 and it is the 7th such number with this property.
CROSSREFS
Sequence in context: A117060 A178460 A351755 * A325920 A351754 A174743
KEYWORD
nonn,more
AUTHOR
Naohiro Nomoto, Oct 09 2000
EXTENSIONS
More terms from Mark Weston (mweston(AT)uvic.ca), Oct 16 2001
a(18) from Giovanni Resta, May 10 2020
a(19) from Kevin P. Thompson, Nov 24 2021
STATUS
approved