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A120483
Decimal expansion of s = sum_{i=1..infinity} (1/c(i))^i, where c(i) is the i-th composite number.
0
2, 7, 9, 8, 9, 3, 6, 6, 3, 3, 5, 7, 5, 0, 2, 3, 8, 3, 2, 3, 2, 2, 7, 6, 0, 4, 1, 4, 3, 4, 1, 5, 0, 1, 6, 1, 5, 1, 2, 4, 0, 1, 1, 8, 7, 6, 4, 2, 4, 4, 0, 3, 1, 2, 8, 7, 0, 3, 5, 8, 5, 0, 9, 2, 2, 3, 1, 5, 3, 3, 9, 8, 6, 1, 6, 7, 2, 6, 6, 6, 9, 7, 2, 6, 4, 9, 5, 8, 0, 9, 0, 4, 0, 0, 9, 0, 7, 6, 6, 2
OFFSET
1,1
EXAMPLE
Sum is (1/4)^1 + (1/6)^2 + (1/8)^3 + (1/9)^4 + (1/10)^5 + ... = 0.279893663...
MATHEMATICA
k = s = 0; Do[If[ !PrimeQ[n], k++; s += (1/n)^k], {n, 2, 100}]; First[RealDigits[N[s, 100]]]
CROSSREFS
Sequence in context: A363078 A377479 A114940 * A124823 A086725 A019950
KEYWORD
cons,nonn
AUTHOR
Ryan Propper, Jul 21 2006
STATUS
approved