OFFSET
0,1
COMMENTS
See A115073 = {1, 8, 9, 352, 530, 697, ...} for the indices of primes.
LINKS
Patrick De Geest, Palindromic Wing Primes: (9)2(9), updated: June 25, 2017.
Makoto Kamada, Factorization of 99...99299...99, updated Dec 11 2018.
Index entries for linear recurrences with constant coefficients, signature (111,-1110,1000).
FORMULA
MAPLE
A332192 := n -> 10^(n*2+1)-1-7*10^n;
MATHEMATICA
Array[ 10^(2 # +1) -1 -7*10^# &, 15, 0]
LinearRecurrence[{111, -1110, 1000}, {2, 929, 99299}, 20] (* Harvey P. Dale, Nov 07 2022 *)
PROG
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
M. F. Hasler, Feb 08 2020
STATUS
approved