29 Nov
2018
29 Nov
'18
12:16 a.m.
APG: "So far the sequence is {4, 5, 13, 53, 8645}, and Hans Havermann has exhausted up to 28000 (possibly further?) without finding any more." Subsequent to my November 2014 calculation, I had another go at it in February 2015. Five months later I had reached 86900, at which point I threw in the towel.