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Value of DIS (Decimal Integer Series) constant based on the sequence of cubes.
1

%I #5 Jul 09 2015 05:34:37

%S 1,0,1,6,7,9,7,7,3,8,2,7,6,8,8,8,1,7,7,0,4,4,6,3,7,4,7,3,1,6,2,4,5,5,

%T 4,3,5,5,6,6,8,8,2,7,7,5,1,2,3,4,7,3,8,7,2,6,3,1,9,3,0,6,2,0,8,3,1,7,

%U 5,5,0,9,8,4,4,0,6,3,9,0,4,0,9,9,8,6,0,8,0,6,8,8,3,3,9,9,8,2,4,7

%N Value of DIS (Decimal Integer Series) constant based on the sequence of cubes.

%F Equals sum_{n>=1} c/100^A055642(c) where c=A000578(n).

%e Equals 0.10167977382768881770446374731...

%p Digits := 220 ;

%p x := 0.0 ;

%p for ndigs from 1 to 200 do

%p # 10^(ndigs-1)<= n^3 < 10^ndigs

%p nmin := ceil(10^((ndigs-1)/3)) ;

%p nmax := floor( root[3](10^(ndigs)-1) ) ;

%p if nmax >= nmin then

%p # sum nmin^3.. nmax^3

%p csu := A000537(nmax)-A000537(nmin-1) ;

%p x := x+evalf(csu/100^ndigs) ;

%p printf("%.120f\n",x) ;

%p end if;

%p end do:

%Y Cf. A258718, A259838.

%K nonn,cons,base

%O 0,4

%A _R. J. Mathar_, Jul 09 2015