The ISC currently accepts either floating point expressions or correct Maple syntax as input. However, for Maple syntax requiring too long for evaluation, a timeout has been implemented.

Factors of ten (and decimal points) are ignored in the input: you should check the results and rescale as required. For example, see 1/640.

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The Inverse Symbolic Calculator (ISC) uses a combination of lookup tables and integer relation algorithms in order to associate a closed form representation with a user-defined, truncated decimal expansion (written as a floating point expression). The lookup tables include a substantial data set compiled by S. Plouffe both before and during his period as an employee at CECM.

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Inverse Symbolic Calculator

Standard lookup results for 0.00156250000

Best guess: 1/64

1/641562500000000000
5/32
Sum(1/2^A020462(n),n=1..inf)1562500000000001
Sum(1/2^A001303(n),n=1..inf)1562500000000088
Sum(1/2^A008380(n),n=1..inf)
Sum(1/2^A002170(n),n=1..inf)1562500000000355
Sum(1/2^A002918(n),n=1..inf)
Sum(1/2^A005399(n),n=1..inf)
Sum(1/2^A001187(n),n=1..inf)1562500000003637
Sum(1/2^A003633(n),n=1..inf)
Sum(1/2^A000561(n),n=1..inf)1562500000005684
Sum(1/2^A005591(n),n=1..inf)
Sum(1/2^A005786(n),n=1..inf)1562500000011368