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A084979
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Palindromes such that the product of the digits + 1 is prime.
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1
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1, 2, 4, 6, 11, 22, 44, 66, 111, 121, 141, 161, 212, 232, 242, 272, 292, 323, 343, 383, 414, 464, 474, 545, 565, 616, 626, 636, 656, 747, 838, 848, 878, 898, 929, 969, 1111, 1221, 1441, 1661, 2112, 2222, 2332, 2552, 2772, 2882, 3223, 3883, 4114, 4444, 4554
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| a(n) >> n^k, where k = log_3(10) = 2.0959....
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EXAMPLE
| E.g. 383 is 3*8*3 = 72, 72+1 = 73 is prime.
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MATHEMATICA
| Select[ Range[4663], FromDigits[ Reverse[ IntegerDigits[ # ]]] == # && PrimeQ[1 + Times @@ IntegerDigits[ # ]] & ]
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CROSSREFS
| Cf. A081988.
Sequence in context: A086379 A096460 A084353 * A049914 A056763 A190071
Adjacent sequences: A084976 A084977 A084978 * A084980 A084981 A084982
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KEYWORD
| nonn,base
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AUTHOR
| Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jun 21 2003
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EXTENSIONS
| Edited, corrected and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 21 2003
Formula by Charles R Greathouse IV (charles.greathouse(AT)case.edu), Aug 02 2010
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