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A147538 Numbers whose binary representation is the concatenation of n 1's and 2n-1 digits 0. 7
2, 24, 224, 1920, 15872, 129024, 1040384, 8355840, 66977792, 536346624, 4292870144, 34351349760, 274844352512, 2198889037824, 17591649173504, 140735340871680, 1125891316908032, 9007164895002624, 72057456598974464 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) is the number whose binary representation is A138119(n).

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000

Index entries for linear recurrences with constant coefficients, signature (12,-32).

FORMULA

a(n) = 2^(2*n-1)*(2^n -1) = A081294(n)*A000225(n). - R. J. Mathar, Nov 09 2008

a(n) = 2*A016152(n). - Omar E. Pol, Nov 13 2008

From Colin Barker, Nov 04 2012: (Start)

a(n) = 12*a(n-1) - 32*a(n-2).

G.f.: 2*x/((1-4*x)*(1-8*x)). (End)

MAPLE

seq(2^(2*n-1)*(2^n -1), n=1..20); # G. C. Greubel, Jan 12 2020

MATHEMATICA

Table[FromDigits[Join[Table[1, {n}], Table[0, {2n - 1}]], 2], {n, 1, 20}] (* Stefan Steinerberger, Nov 11 2008 *)

PROG

(PARI) vector(20, n, 2^(2*n-1)*(2^n -1)) \\ G. C. Greubel, Jan 12 2020

(MAGMA) [2^(2*n-1)*(2^n -1): n in [1..20]]; // G. C. Greubel, Jan 12 2020

(Sage) [2^(2*n-1)*(2^n -1) for n in (1..20)] # G. C. Greubel, Jan 12 2020

(GAP) List([1..20], n-> 2^(2*n-1)*(2^n -1)); # G. C. Greubel, Jan 12 2020

CROSSREFS

Cf. A138119.

Cf. A016152. - Omar E. Pol, Nov 13 2008

Sequence in context: A174668 A302444 A121213 * A180388 A288270 A221653

Adjacent sequences:  A147535 A147536 A147537 * A147539 A147540 A147541

KEYWORD

base,easy,nonn

AUTHOR

Omar E. Pol, Nov 06 2008

EXTENSIONS

Extended by R. J. Mathar and Stefan Steinerberger, Nov 09 2008

STATUS

approved

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Last modified September 27 15:29 EDT 2020. Contains 337383 sequences. (Running on oeis4.)