A330468 Numbers k where the difference (least prime > 10^k) - (greatest prime < 10^k) sets a record.
1, 3, 4, 9, 16, 21, 24, 28, 34, 66, 82, 92, 117, 122, 135, 218, 232, 314, 387, 443, 478, 617, 652, 787, 1031, 1157, 1440, 1625, 1872, 1920, 2038, 2424, 2692, 3235, 3331, 3798, 4944, 5202, 5241, 5938, 7572, 7847
Offset: 1
Examples
a(1) = 1: 11 - 7 = 4; a(2) = 3: 1009 - 997 = 12, whereas 101 - 97 = 4 <= a(1).
Programs
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PARI
d=0;for(k=1,500,my(t=10^k,dd=nextprime(t)-precprime(t));if(dd>d,print1(k,", ");d=dd))
Extensions
More terms from Jinyuan Wang, Mar 01 2020
a(37)-a(42) from Giovanni Resta, Mar 15 2020