cp's OEIS Frontend

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.

A167293 Long legs of Pythagorean triangles that are not divisible by any other long leg of a Pythagorean triangle.

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%I A167293 #2 Mar 30 2012 17:28:33
%S A167293 4,15,21,35,55,77,91,99,117,143,153,171,187,209,221,247,253,299,323,
%T A167293 325,377,391,403,425,437,475,493,527,551,575,589,621,629,667,697,703,
%U A167293 713,725,775,779,783,817,837,851,899,925,943,957,989,999,1023,1025,1073
%N A167293 Long legs of Pythagorean triangles that are not divisible by any other long leg of a Pythagorean triangle.
%C A167293 All long legs of Pythagorean triangles (A009023) are multiples of these values, so these values can be thought of as "primes" of the sequence of long legs.
%o A167293 (PARI) llp = vector(60); np = 1; llp[np] = 4;
%o A167293 notdiv(k) = for(j=1,np,if(k%llp[j],1,return(0)));return(1);
%o A167293 isLongLeg(n) = local(b);b=0;for(k=1,n-1,if(issquare(k^2+n^2),b=1));return(b);
%o A167293 for(k=4,1175,if(notdiv(k),if(isLongLeg(k),np+=1;llp[np]=k)))
%o A167293 for(n=1,60,print1(llp[n],", "))
%Y A167293 A009023
%K A167293 nonn
%O A167293 1,1
%A A167293 _Gerald McGarvey_, Nov 01 2009
%E A167293 Comments and PARI program corrected by _Gerald McGarvey_, Nov 03 2009