A190801 Least semiprime whose prime factors differ by n!.
6, 15, 55, 145, 889, 5089, 55561, 927889, 6169249, 39916921, 678585889, 13891047241, 417210398089, 1656387533161, 56229997825849, 481224167424529, 11026310270976961, 236887827111937369, 10826413936386055921
Offset: 1
Keywords
Examples
a(5) = 889 because 889 = 7 * 127 , and 127 - 7 = 120 = 5!
Programs
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Mathematica
f[n_] := Block[{p=2}, While[! PrimeQ[p+n!], p=NextPrime[p]]; p*(p+n!)]; Table[f[n], {n, 60}]
Comments