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A128092
a(n) = largest multiple of n which is <= 2^n.
3
2, 4, 6, 16, 30, 60, 126, 256, 504, 1020, 2046, 4092, 8190, 16380, 32760, 65536, 131070, 262134, 524286, 1048560, 2097144, 4194300, 8388606, 16777200, 33554425, 67108860, 134217702, 268435440, 536870910, 1073741820, 2147483646
OFFSET
1,1
FORMULA
a(n) = n*floor(2^n/n) = n*A000799(n).
a(n) = 2^n - (2^n mod n). - Chai Wah Wu, Aug 24 2023
MAPLE
a:=n->n*floor(2^n/n): seq(a(n), n=1..37); # Emeric Deutsch, Feb 16 2007
MATHEMATICA
f[n_] := n*Floor[2^n/n]; Array[f, 33] (* Ray Chandler, Feb 19 2007 *)
PROG
(Python)
def A128092(n): return (m:=1<<n)-(m%n) # Chai Wah Wu, Aug 24 2023
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Feb 14 2007
EXTENSIONS
Extended by Emeric Deutsch and Ray Chandler, Feb 19 2007
STATUS
approved