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A153432
Numbers m such that all ten numbers 10^k*m+1; k=0,1,...,9 are prime.
2
15538734736, 28034367522, 41221375552, 89468493268, 92220460962, 95951017078, 105627706800, 108012908976, 147689513538, 161055865908, 177073756566, 181921823202, 185137153012, 192336309046, 212463686778
OFFSET
1,1
COMMENTS
If m & n are in the sequence, k<10 and r=m*n*10^k -1 is prime then r has at least k+1 representations of the form p*q-(p+q)where p & q are prime.
LINKS
Carlos Rivera, Puzzle 482. Two Bergot questions, The Prime Puzzles & Problems Connection.
FORMULA
a(n) >> n log^10 n. - Charles R Greathouse IV, Dec 29 2024
CROSSREFS
Subsequence of A006093 and of A008596.
Sequence in context: A023050 A233704 A378315 * A349324 A022241 A186016
KEYWORD
nonn,more
AUTHOR
Farideh Firoozbakht, Mar 31 2009
STATUS
approved