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A083974
Smallest palindromic prime containing exactly n 3's.
9
3, 313, 13331, 33533, 1333331, 3331333, 323333323, 13333633331, 31333333313, 1333335333331, 3233333333323, 133333353333331, 332333333333233, 333333313333333, 33233333333333233, 1333333336333333331, 3333333313133333333, 133333333383333333331
OFFSET
1,1
LINKS
MATHEMATICA
Table[d = 3; i = 1;
While[ x = IntegerDigits[Prime[i]];
x != Reverse[x] || Count[x, d] != n , i++];
FromDigits[x], {n, 1, 6}] (* Robert Price, Mar 25 2019 *)
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 21 2003
EXTENSIONS
More terms from Giovanni Resta, Feb 08 2006
STATUS
approved