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 A138144 Palindromes formed from the reflected decimal expansion of the concatenation of 1, 1 and infinite 0's. 12
 1, 11, 111, 1111, 11011, 110011, 1100011, 11000011, 110000011, 1100000011, 11000000011, 110000000011, 1100000000011, 11000000000011, 110000000000011, 1100000000000011, 11000000000000011, 110000000000000011 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) is also A147595(n) written in base 2. [From Omar E. Pol, Nov 08 2008] LINKS Index entries for linear recurrences with constant coefficients, signature (11,-10). FORMULA a(n) = 11+11*10^(n-2) for n>3. a(n) = 11*a(n-1)-10*a(n-2). G.f.: -x*(10*x^2-1)*(10*x^2+1) / ((x-1)*(10*x-1)). - Colin Barker, Sep 15 2013 EXAMPLE n .... a(n) 1 .... 1 2 .... 11 3 .... 111 4 .... 1111 5 .... 11011 6 .... 110011 7 .... 1100011 8 .... 11000011 9 .... 110000011 10 ... 1100000011 MATHEMATICA LinearRecurrence[{11, -10}, {1, 11, 111, 1111, 11011}, 20] (* Harvey P. Dale, Aug 21 2016 *) PROG (PARI) Vec(-x*(10*x^2-1)*(10*x^2+1)/((x-1)*(10*x-1)) + O(x^100)) \\ Colin Barker, Sep 15 2013 CROSSREFS Cf. A000533. Cf. A138118, A138119, A138120, A138145, A138146, A138721, A138826, A147595. [From Omar E. Pol, Nov 08 2008] Sequence in context: A283850 A283605 A083440 * A284243 A283005 A283256 Adjacent sequences:  A138141 A138142 A138143 * A138145 A138146 A138147 KEYWORD easy,nonn,base AUTHOR Omar E. Pol, Mar 29 2008 EXTENSIONS Better definition. - Omar E. Pol, Nov 15 2008 STATUS approved

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Last modified May 21 23:19 EDT 2019. Contains 323467 sequences. (Running on oeis4.)