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 A263431 Near-repdigit primes with only digits 9 and a single 8 in decimal expansion. 2
 89, 8999, 98999, 99989, 989999, 9899999, 89999999, 99899999, 99998999, 99999989, 998999999, 98999999999, 99989999999, 999998999999, 999999999899, 999999999989, 99899999999999, 99999899999999, 99999999899999, 999999899999999, 999999999989999, 999999999999989 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Felix Fröhlich, Table of n, a(n) for n = 1..200 PROG (PARI) a002283(n) = 10^n-1 a011557(n) = 10^n num(n, k) = a002283(n)-a011557(k) terms(n) = i=0; x=1; while(x > 0, y=x-1; while(y >= 0, if(ispseudoprime(num(x, y)), print1(num(x, y), ", "); i++); if(i==n, break({2})); y--); x++) terms(30) \\ print initial thirty terms CROSSREFS Cf. A020472, A065074, A069661, A105975, A178007. Sequence in context: A264135 A264020 A020472 * A093948 A116254 A086695 Adjacent sequences:  A263428 A263429 A263430 * A263432 A263433 A263434 KEYWORD nonn,base,easy AUTHOR Felix Fröhlich, Oct 18 2015 STATUS approved

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Last modified October 20 22:05 EDT 2019. Contains 328291 sequences. (Running on oeis4.)