This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A135526 #12 Jun 23 2024 07:25:23
%S A135526 1,6,33,95,188,288,388,488,588,688,788,888,988,1088,1188,1288,1388,
%T A135526 1488,1588,1688,1788,1888,1988,2088,2188,2288,2388,2488,2588,2688,
%U A135526 2788,2888,2988,3088,3188,3288,3388,3488,3588,3688,3788,3888,3988,4088,4188,4288
%N A135526 Number of sums payable using exactly n banknotes of denominations 1, 5, 10, 20, 50, 100 (change allowable).
%C A135526 Terms and formula from _Max Alekseyev_ and _Robert Israel_.
%H A135526 G. C. Greubel, <a href="/A135526/b135526.txt">Table of n, a(n) for n = 0..1000</a>
%H A135526 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1).
%F A135526 a(n) = 100*n - 212 for n>=4.
%F A135526 From _G. C. Greubel_, Oct 17 2016: (Start)
%F A135526 a(n) = 2*a(n-1) - a(n-2), for n >= 4.
%F A135526 G.f.: (1 + 4*x + 22*x^2 + 35*x^3 + 31*x^4 + 7*x^5)/(1-x)^2.
%F A135526 E.g.f.: (1/6)*( 1278 + 708*x + 135*x^2 + 7*x^3 - 24*(53 - 25*x)*exp(x) ). (End)
%t A135526 Join[{1,6,33,95}, LinearRecurrence[{2,-1},{188,288},25]] (* or *) Join[{1,6,33,95}, Table[100*n -212, {n,4,25}]] (* _G. C. Greubel_, Oct 17 2016 *)
%o A135526 (PARI) a(n)=if(n>3,100*n-212,[1,6,33,95][n+1]) \\ _Charles R Greathouse IV_, Jun 23 2024
%Y A135526 Cf. A124146, A135137, A135454.
%K A135526 nonn,easy
%O A135526 0,2
%A A135526 _Zak Seidov_, Feb 20 2008
%E A135526 Extended by _Max Alekseyev_, Mar 04 2009