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 A094622 Expansion of x*(11+20*x)/((1-x)*(1-10*x^2)). 2
 0, 11, 31, 141, 341, 1441, 3441, 14441, 34441, 144441, 344441, 1444441, 3444441, 14444441, 34444441, 144444441, 344444441, 1444444441, 3444444441, 14444444441, 34444444441, 144444444441, 344444444441, 1444444444441 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Previous name: Sequence whose n-th term's digits sum to 2n. a(n) is the digit reversal of A094621(n). LINKS Index entries for linear recurrences with constant coefficients, signature (1,10,-10). FORMULA G.f.: x*(11+20*x)/((1-x)*(1-10*x^2)); a(n) = (10^(n/2)*(31 + 13*sqrt(10) + (31 - 13*sqrt(10))*(-1)^n)/2 - 31)/9. E.g.f.: (1/18)*exp(-sqrt(10)*x)*(31-13*sqrt(10)+(31+13*sqrt(10))*exp(2*sqrt(10)*x)-62*exp(x+sqrt(10)*x)). - Stefano Spezia, Sep 04 2019 MATHEMATICA LinearRecurrence[{1, 10, -10}, {0, 11, 31}, 30] (* Harvey P. Dale, May 03 2016 *) CROSSREFS Cf. A094620, A094621. Sequence in context: A082712 A049090 A181150 * A193645 A190781 A001604 Adjacent sequences:  A094619 A094620 A094621 * A094623 A094624 A094625 KEYWORD easy,nonn,base AUTHOR Paul Barry, May 15 2004 STATUS approved

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Last modified December 11 18:34 EST 2019. Contains 329925 sequences. (Running on oeis4.)