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A346046
Decimal expansion of Sum_{k>=1} 1/A053657(k).
1
1, 5, 6, 2, 7, 6, 0, 9, 3, 4, 4, 4, 6, 9, 3, 7, 4, 5, 5, 0, 1, 4, 2, 2, 7, 3, 0, 8, 4, 8, 9, 5, 3, 0, 3, 0, 1, 9, 1, 3, 8, 7, 6, 8, 8, 9, 0, 8, 2, 0, 4, 0, 0, 1, 5, 0, 4, 8, 3, 3, 3, 6, 8, 0, 8, 5, 8, 4, 1, 0, 8, 5, 3, 7, 9, 2, 5, 4, 1, 2, 0, 5, 2, 7, 9, 4, 5, 4, 4, 6, 2, 0, 0, 6, 2, 3, 0, 4, 7, 7
OFFSET
1,2
COMMENTS
This constant is irrational (Mingarelli, 2013).
LINKS
Angelo B. Mingarelli, Abstract factorials, Notes on Number Theory and Discrete Mathematics, Vol. 19, No. 4 (2013), pp. 43-76 (see p. 60); arXiv preprint, arXiv:0705.4299 [math.NT], 2007-2012.
EXAMPLE
1.56276093444693745501422730848953030191387688908204...
MATHEMATICA
f[n_] := Product[p^Sum[Floor[(n - 1)/((p - 1) p^k)], {k, 0, n}], {p, Prime[Range[n]]}]; RealDigits[Sum[1/f[n], {n, 1, 100}], 10, 100] [[1]]
CROSSREFS
Cf. A053657.
Sequence in context: A038690 A154801 A253094 * A217015 A107825 A201332
KEYWORD
nonn,cons
AUTHOR
Amiram Eldar, Jul 02 2021
STATUS
approved