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A128848 Numerators of the continued fraction convergents of the decimal concatenation of the twin prime pairs. 0

%I #4 Oct 01 2013 21:35:21

%S 0,1,1,5,16,37,53,355,1118,3709,8536,12245,204456,421157,1467927,

%T 1889084,5246095,7135179,12381274,93804097,106185371,306174839,

%U 412360210,718535049,1130895259,2980325567,16032523094,35045371755

%N Numerators of the continued fraction convergents of the decimal concatenation of the twin prime pairs.

%F The twin prime pairs 3,5,5,7,11,13,17,19... are concatenated and then preceded by a decimal point to create the fraction N = .3557111317192931... This number is then evaluated with n=0,m=steps to iterate,x = N, a(0)=floor(N) using the loop: do a(n)=floor(x) x=1/(x-a(n)) n=n+1 loop until n=m

%o (PARI) cattwinP(n) = { a=".";forprime(x=3,n,if(ispseudoprime(x+2),a=concat(a,Str(x)); a=concat(a,Str(x+2))));a=eval(a) } cfrac2(m,f) = { default(realprecision,1000); cf = vector(m+10); cf = contfrac(f); for(m1=1,m-1, r=cf[m1+1]; forstep(n=m1,1,-1, r = 1/r; r+=cf[n];); numer=numerator(r); denom=denominator(r); print1(numer","); ) }

%K frac,nonn,base

%O 0,4

%A _Cino Hilliard_, Apr 16 2007

%E Edited by _Charles R Greathouse IV_, Apr 25 2010

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Last modified April 24 20:08 EDT 2024. Contains 371963 sequences. (Running on oeis4.)