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 A138118 Concatenation of 2n-1 digits 1 and n digits 0. 10
 10, 11100, 11111000, 11111110000, 11111111100000, 11111111111000000, 11111111111110000000, 11111111111111100000000, 11111111111111111000000000, 11111111111111111110000000000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(n) is also A147537(n) written in base 2. [From Omar E. Pol, Nov 08 2008] LINKS Index entries for linear recurrences with constant coefficients, signature (1010,-10000) FORMULA O.g.f.: 10*(1+100x)/[(-1+1000x)*(-1+10x)]. a(n)=A100706(n)*10^n = 10*a(n-1)+11*1000^n. - R. J. Mathar, Apr 03 2008 a(n)=-(10/9)*10^(n-1)+(100/9)*1000^(n-1), with n>=1 - Paolo P. Lava, Jul 15 2008 EXAMPLE n .......... a(n) 1 ........... 10 2 ......... 11100 3 ....... 11111000 4 ..... 11111110000 5 ... 11111111100000 MATHEMATICA FromDigits/@Table[Join[PadRight[{}, 2n-1, 1], PadRight[{}, n, 0]], {n, 15}] (* Harvey P. Dale, Dec 09 2011 *) CROSSREFS Cf. A138147, A138721. Cf. A147537. Sequence in context: A267705 A086164 A138119 * A267130 A267850 A267206 Adjacent sequences:  A138115 A138116 A138117 * A138119 A138120 A138121 KEYWORD easy,nonn,base AUTHOR Omar E. Pol, Mar 29 2008 STATUS approved

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Last modified October 23 23:51 EDT 2019. Contains 328379 sequences. (Running on oeis4.)