The coin flips I entered passed the site's tests for randomness. I generated them by first picking an arbitrary integer in [0,59]. I then (using simple mental a

The coin flips I entered passed the site's tests for randomness. I generated them by first picking an arbitrary integer in [0,59]. I then (using simple mental arithmetic) used that integer to seed a PRNG by George Marsaglia [1] to generate a stream of pseudo-random decimal digits. For each digit, if it was in [0,7], then I took the 3-low order bits of its binary representation, in order from least significant to most significant bit (0=tails, 1=heads). If the digit was 8 or 9, I discarded it. Since each non-discarded digit gave me 3 bits, I needed 34 non-discarded digits to get 100 bits. Note that the PRNG I used has period 59, and only 20% of the output digits would have to be discarded. Therefore one could use this approach to generate up to 141 pseudo-random bits. [1] Marsaglia, George. "How to generate random number sequences (in your head)" (https://groups.google.com/d/msg/sci.math/6BIYd0cafQo/Ucipn_5T_TMJ https://groups.google.com/d/msg/sci.math/6BIYd0cafQo/Ucipn_5...)