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 A069760 #19 Aug 22 2025 02:18:10
%S A069760 47,287,959,2399,5039,9407,16127,25919,39599,58079,82367,113567,
%T A069760 152879,201599,261119,332927,418607,519839,638399,776159,935087,
%U A069760 1117247,1324799,1559999,1825199,2122847
%N A069760 Frobenius number of the numerical semigroup generated by consecutive centered square numbers.
%C A069760 The Frobenius number of a numerical semigroup generated by relatively prime integers a_1,...,a_n is the largest positive integer that is not a nonnegative linear combination of a_1,...,a_n. Since consecutive centered squares are relatively prime, they generate a numerical semigroup with a Frobenius number. The Frobenius number of a 2-generator semigroup <a,b> is ab-a-b.
%H A069760 R. Fröberg, C. Gottlieb and R. Häggkvist, <a href="https://gdz.sub.uni-goettingen.de/id/PPN362162808_0035">On numerical semigroups</a>, Semigroup Forum, 35 (1987), 63-83 (for definition of Frobenius number).
%H A069760 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1).
%F A069760 a(n) = 4*n^4+16*n^3+20*n^2+8*n-1.
%F A069760 a(n) = 5*a(n-1)-10*a(n-2) +10*a(n-3)-5*a(n-4)+a(n-5). - _Harvey P. Dale_, Apr 25 2011
%F A069760 G.f.: x*(47+52*x-6*x^2+4*x^3-x^4)/(1-x)^5. - _Colin Barker_, Feb 14 2012
%e A069760 a(1)=47 because 47 is not a nonnegative linear combination of 5 and 13, but all integers greater than 47 are.
%t A069760 Table[4n^4+16n^3+20n^2+8n-1,{n,30}] (* or *) LinearRecurrence[ {5,-10,10,-5,1},{47,287,959,2399,5039},30] (* _Harvey P. Dale_, Apr 25 2011 *)
%Y A069760 Cf. A001844, A037165, A059769, A069755-A069764.
%K A069760 easy,nonn
%O A069760 1,1
%A A069760 Victoria A Sapko (vsapko(AT)canes.gsw.edu), Apr 09 2002