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A358030
Decimal expansion of the constant Sum_{j>=0} j!!/prime(j)#, where prime(j)# indicates the j-th primorial number and j!! is the double factorial of j.
0
1, 9, 7, 9, 7, 7, 0, 6, 3, 3, 0, 6, 8, 0, 2, 8, 6, 8, 1, 9, 7, 0, 0, 0, 6, 0, 7, 5, 4, 1, 5, 6, 5, 4, 5, 0, 0, 6, 9, 3, 1, 1, 9, 3, 1, 7, 9, 8, 3, 8, 7, 9, 5, 6, 2, 4, 2, 0, 6, 4, 0, 0, 3, 4, 6, 5, 4, 7, 6, 1, 5, 6, 3, 1, 4, 5, 1, 2, 5, 0, 1, 0, 2, 0, 2, 2, 6
OFFSET
1,2
FORMULA
Equals Sum_{j>=0} A006882(j)/A002110(j).
EXAMPLE
1.979770633068...
MATHEMATICA
primorial[n_?Positive] := Product[Prime[i], {i, 1, n}];
RealDigits[1 + Sum[i!!/primorial[i], {i, 1, 500}], 10, 107][[1]]
CROSSREFS
KEYWORD
cons,easy,nonn
AUTHOR
Marco Ripà, Nov 12 2022
STATUS
approved