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A100413 Numbers k such that k is reversal(k)-th even composite number (k is A004086(k)-th even composite number).

%I A100413 #35 Apr 14 2023 10:52:41
%S A100413 52,592,5992,59992,599992,5999992,59999992,599999992,5999999992,
%T A100413 59999999992,599999999992,5999999999992,59999999999992,
%U A100413 599999999999992,5999999999999992,59999999999999992,599999999999999992
%N A100413 Numbers k such that k is reversal(k)-th even composite number (k is A004086(k)-th even composite number).
%H A100413 G. C. Greubel, <a href="/A100413/b100413.txt">Table of n, a(n) for n = 1..500</a>
%H A100413 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (11,-10).
%F A100413 a(n) = 6*10^n - 8.
%F A100413 a(n) = 2*(A086943(n) + 3). - _Martin Ettl_, Nov 08 2012
%F A100413 From _Colin Barker_, Oct 14 2014: (Start)
%F A100413 a(n) = 10*a(n-1) + a(n-2) - 10*a(n-3).
%F A100413 G.f.: 4*x*(13+5*x)/((1-x)*(1-10*x)). (End)
%F A100413 E.g.f.: 2 (1 - 4*exp(x) + 3*exp(10*x)). - _G. C. Greubel_, Apr 13 2023
%e A100413 592 is in the sequence because 592 is the 295th even composite number.
%p A100413 A100413:=n->6*10^n-8; seq(A100413(n), n=1..20); # _Wesley Ivan Hurt_, Apr 06 2014
%t A100413 Table[6*10^n-8, {n,20}]
%o A100413 (Maxima) A100413(n):=6*10^n-8$
%o A100413 makelist(A100413(n),n,1,17); /* _Martin Ettl_, Nov 08 2012 */
%o A100413 (PARI) Vec(4*x*(5*x+13)/((x-1)*(10*x-1)) + O(x^100)) \\ _Colin Barker_, Oct 14 2014
%o A100413 (Magma) [6*10^n -8: n in [1..20]]; // _G. C. Greubel_, Apr 13 2023
%o A100413 (SageMath) [6*10^n -8 for n in range(1,21)] # _G. C. Greubel_, Apr 13 2023
%Y A100413 Cf. A004086, A086943, A100412.
%K A100413 base,easy,nonn
%O A100413 1,1
%A A100413 _Farideh Firoozbakht_, Dec 08 2004