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 A135285 #5 Sep 10 2016 15:57:46 %S A135285 10,24,126,294,858,1704,3528,5082,10296,11526,18894,22320,32208,36666, %T A135285 38976,51744,57330,72618,79212,96996,120684,175968,186162,212922, %U A135285 271914,324300,359382,381282,411504,434790,655278,674856,684726,735282,776904 %N A135285 Sum of staircase twin primes according to the rule: top * bottom - next top. %C A135285 While there is multiplication and subtraction in the generation of this sequence, it is still called a sum because the arithmetic processes -,*,/ are derived from addition. %F A135285 We list the twin primes in staircase fashion as in A135283. Then a(n) = tl(n) * tu(n) + (-tl(n+1)). %F A135285 a(n) = A037074(n) -A001359(n+1). - _R. J. Mathar_, Sep 10 2016 %o A135285 (PARI) g(n) = for(x=1,n,y=twinu(x) * twinl(x) - twinl(x+1);print1(y",")) twinl(n) = / *The n-th lower twin prime. */ { local(c,x); c=0; x=1; while(c<n, if(ispseudoprime(prime(x)+2),c++); x++; ); return(prime(x-1)) } twinu(n) = /* The n-th upper twin prime. */ { local(c,x); c=0; x=1; while(c<n, if(isprime(prime(x)+2),c++); x++; ); return(prime(x)) } %K A135285 nonn %O A135285 1,1 %A A135285 _Cino Hilliard_, Dec 03 2007