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A230047
Palindromic primes with nondecreasing product of digits.
1
2, 3, 5, 7, 181, 191, 313, 353, 373, 383, 727, 757, 787, 797, 17971, 19891, 19991, 34843, 35753, 36563, 37573, 38783, 74747, 75557, 76667, 77977, 78787, 78887, 79997, 1987891, 1988891, 1998991, 3479743, 3487843, 3569653, 3586853, 3589853, 3689863, 3698963
OFFSET
1,1
COMMENTS
a(1) = 2; a(n+1) is the smallest palindromic prime with product of digits >= product of digits of a(n).
LINKS
MATHEMATICA
a = {}; t = 0; Do[z = n*10^(IntegerLength[n] - 1) + FromDigits@Rest@Reverse@IntegerDigits[n]; If[PrimeQ[z], s = Apply[Times, IntegerDigits[z]]; If[s >= t, t = s; AppendTo[a, z]]], {n, 10^4}]; a
CROSSREFS
Sequence in context: A230046 A098463 A064155 * A230042 A230045 A069803
KEYWORD
nonn,base
AUTHOR
Shyam Sunder Gupta, Oct 06 2013
STATUS
approved