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A354676
a(n) = number of near-Wieferich primes with |A| <= 100 less than 10^n.
3
3, 24, 105, 154, 213, 243, 268, 288, 307
OFFSET
1,1
COMMENTS
n | a(n) | A006880(n) | a(n)/A006880(n)*100
--------------------------------------------
1 | 3 | 4 | 75.000000
2 | 24 | 25 | 96.000000
3 | 105 | 168 | 62.500000
4 | 154 | 1229 | 12.530512
5 | 213 | 9592 | 2.220600
6 | 243 | 78498 | 0.309562
7 | 268 | 664579 | 0.040326
8 | 288 | 5761455 | 0.004998
9 | 307 | 50847534 | 0.000603
PROG
(PARI) a258367(n) = abs(centerlift(Mod(2, n^2)^((n-1)/2))\/n) \\ after Charles R Greathouse IV in A258367
my(i=0, x=10); forprime(p=3, , if(p > x, print1(i, ", "); x=10*x); if(a258367(p) <= 100, i++))
KEYWORD
nonn,hard,more
AUTHOR
Felix Fröhlich, Jun 02 2022
STATUS
approved