A157414 Decimal expansion of Sum_{q = semiprimes = A001358} 1/(q*2^q).

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

Offset

0,3

Links

Table of n, a(n) for n=0..104.

R. J. Mathar, Series of reciprocal powers of k-almost primes, arxiv:0803.0900, eq. (66).

Formula

A002162 = Sum_{n>=1} 1/(n*2^n) = 1/2 + A157413 + this_constant_here + equivalent terms of higher order k-almost primes.

Example

0.0185502662799497065892654852882047774... = 1/(4*2^4)+1/(6*2^6)+1/(9*2^9)+1/(10*2^10)+... = Sum_{i>=1} 1/(A001358(i)*2^A001358(i)).

Crossrefs

Cf. A001358.

Sequence in context: A000052 A072991 A235995 * A021543 A257436 A201295

Adjacent sequences: A157411 A157412 A157413 * A157415 A157416 A157417

Keyword

cons,nonn

Author

R. J. Mathar, Feb 28 2009

Status

approved