|
|
A162473
|
|
Write n in binary n times and concatenate (see example). a(n) is the decimal equivalent.
|
|
2
|
|
|
1, 10, 63, 2340, 23405, 224694, 2097151, 2290649224, 41231686041, 733007751850, 12900936432571, 225179981368524, 3903119677054429, 67253754435399406, 1152921504606846975, 623961713349486025654800, 21214698253882524872263217, 718803893778607901554330194
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
LINKS
|
|
|
FORMULA
|
|
|
EXAMPLE
|
The binary representations of the first few terms are 1, 1010, 111111, 100100100100, 101101101101101.
|
|
MAPLE
|
A070939 := proc(n) max(1, ilog2(n)+1) ; end: A162473 := proc(n) local bid, a062383; bid := A070939(n) ; a062383 := 2^bid ; n*(a062383^n-1)/(a062383-1) ; end: seq(A162473(n), n=1..30) ; # R. J. Mathar, Jul 06 2009
# second Maple program:
a:= n-> Bits[Join](map(x-> x[], [Bits[Split](n)$n])):
|
|
MATHEMATICA
|
Table[FromDigits[Flatten[Table[IntegerDigits[n, 2], {n}]], 2], {n, 20}] (* Harvey P. Dale, Jun 15 2021 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
base,nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|