A350830 Number of prime 10-tuples (or decaplets) with initial member (A257127) between 10^(n-1) and 10^n.
0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 4, 15, 81, 357, 1685, 8256
Offset: 1
Examples
a(2) = 1 because 11 is the only two-digit prime to start a prime decaplet, i.e., member of A257127. a(n) = 0 for all other n < 10 because the next larger prime decaplet is made of 10-digit primes, A257127(2) = 9853497737 and successors. a(10) = 1 because there is only one prime decaplet made of 10-digit primes. a(11) = 4 because there are only four terms in A257127 (for indices n = 3..6) which have 11 digits.
Links
- Norman Luhn, The big database of "The smallest prime k-tuplets", section "10-uplets": up to 10^20 as of March 2022.
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