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A139564
Number of primes < 10^(2n) - sum of primes < 10^n.
2
0, 8, 169, 2371, 25059, 655974, 57509995, 1616756446, 28550646649, 442195486325, -2830020810398, 208945571225276, 11214798494956489, 307494657722438109, 8565236469871178577
OFFSET
0,2
COMMENTS
Pi(x) is the prime counting function or the number of primes <= x. SumP(x) = sum of primes <= x.
For 2n = 20, we get a negative value -2830020810398. This seems strange to me.
I emailed Marc Deleglise on this. The links shows the Pi(x) and SumP(x) values.
FORMULA
a(n) = A006880(2*n) - A046731(n). - Amiram Eldar, Jun 30 2024
CROSSREFS
KEYWORD
sign,more
AUTHOR
Cino Hilliard, Jun 11 2008
EXTENSIONS
a(12)-a(14) from Amiram Eldar, Jun 30 2024
STATUS
approved