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A340902
Distance from the largest prime with less than 10^n decimal digits to 10^(10^n-1).
0
63, 621, 6101, 11333, 59511, 172473
OFFSET
1,1
COMMENTS
The prime number related to a(n) is the prime immediately preceding the prime related to A096548(n).
a(5) and a(6) appear to have been first found by Patrick De Geest.
LINKS
factordb.com, 10^999 - 6101, contains primality certificate related to a(3).
factordb.com, 10^9999 - 11333, contains primality certificate related to a(4).
Henri Lifchitz, Renaud Lifchitz, 10^99999 - 59511, related to a(5).
Henri Lifchitz, Renaud Lifchitz, 10^999999 - 172473, related to a(6).
Wikipedia, Titanische Primzahl, in German.
FORMULA
a(n) = 10^(10^n-1) - precprime(10^(10^n-1)) = A064722(10^A002283(n)).
EXAMPLE
a(4) = 11333 because 10^9999 - 11333 is the largest prime not exceeding 10^9999.
a(5) = 59511 because 10^99999 - 59511 is the largest prime not exceeding 10^99999.
CROSSREFS
Sequence in context: A179537 A184448 A228262 * A181125 A228221 A022522
KEYWORD
nonn,base,more,hard
AUTHOR
Jeppe Stig Nielsen, Jan 26 2021
STATUS
approved