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%I #7 Nov 17 2024 16:41:09
%S 17,56,1888
%N Numbers k such that 1 + 1234567890*Sum_{i=1..k} 10^(10i-9) is prime.
%C The first two terms are given in the linked source in "Table 42: Ten Types of 'Rare' Prime Numbers" for entry "B. Sequential prime of the type: (1234567890)n 1", which designates that 1234567890 is concatenated n times and then 1 is appended. 1888, found by PrimeForm using recurrence mode, corresponds to an 18881-digit probable prime. There are no other terms <= 3000.
%C There are no other terms <= 10000. - _Michael S. Branicky_, Nov 17 2024
%H R. Ondrejka, <a href="http://www.utm.edu/research/primes/lists/top_ten/">The Top Ten: a Catalogue of Primal Configurations</a>
%K bref,hard,more,nonn
%O 1,1
%A _Rick L. Shepherd_, May 03 2006