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 A209328 Decimal expansion of the sum of the inverse twin prime products. 1
 1, 0, 7, 9, 8, 3, 9, 7, 4, 9, 5 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Summation up to the lesser prime(100000) gives 0.1079839703839.., summation up to the lesser prime(5000000) gives 0.10798397490956.. and summation up to the lesser prime(100000000) gives 0.107983974949.. The constant splits Brun's constant B=A065421 into two portions: define L=sum_{n>=1} 1/A001359(n) and U=sum_{n>=1} 1/A006512(n). Then B=U+L and this constant here = (L-U)/2. This leads to the estimates L=1.059064 and U=0.843096. - R. J. Mathar, Feb 05 2013 LINKS EXAMPLE 0.10798397495... =1/(3*5) + 1/(5*7) + 1/(11*13) + .. = sum_{n>=1} 1/A037074(n). CROSSREFS Sequence in context: A182688 A256924 A259069 * A228049 A154943 A126041 Adjacent sequences:  A209325 A209326 A209327 * A209329 A209330 A209331 KEYWORD nonn,cons,more AUTHOR R. J. Mathar, Jan 19 2013 STATUS approved

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Last modified February 21 19:02 EST 2020. Contains 332109 sequences. (Running on oeis4.)