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A147539 Numbers whose binary representation is the concatenation of n 1's, 2n-1 digits 0 and n 1's. 6
5, 99, 1799, 30735, 507935, 8257599, 133169279, 2139095295, 34292630015, 549218943999, 8791798056959, 140703128621055, 2251524935786495, 36026597995724799, 576443160117411839, 9223231299366486015 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) is the number whose binary representation is A138120(n).

LINKS

Table of n, a(n) for n=1..16.

Index entries for linear recurrences with constant coefficients, signature (27,-202,432,-256).

FORMULA

a(n) = 2^n-1+2^(4n-1)-2^(3n-1). - R. J. Mathar, Nov 09 2008

G.f.: x*(136*x^2-36*x+5)/((x-1)*(2*x-1)*(8*x-1)*(16*x-1)). - Colin Barker, Nov 04 2012

a(n) = 27*a(n-1) - 202*a(n-2) + 432*a(n-3) - 256*a(n-4). - Wesley Ivan Hurt, Jan 11 2017

MAPLE

A147539:=n->2^n-1+2^(4*n-1)-2^(3*n-1): seq(A147539(n), n=1..30); # Wesley Ivan Hurt, Jan 11 2017

MATHEMATICA

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

LinearRecurrence[{27, -202, 432, -256}, {5, 99, 1799, 30735}, 20] (* Harvey P. Dale, Aug 28 2017 *)

PROG

(MAGMA) [2^n-1+2^(4*n-1)-2^(3*n-1) : n in [1..20]]; // Wesley Ivan Hurt, Jan 11 2017

CROSSREFS

Cf. A138120.

Sequence in context: A301307 A277418 A318061 * A266610 A156276 A322715

Adjacent sequences:  A147536 A147537 A147538 * A147540 A147541 A147542

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 21 22:07 EDT 2019. Contains 327283 sequences. (Running on oeis4.)