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Search: id:A059758
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| A059758 |
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Undulating palindromic primes: numbers that are prime, palindromic in base 10, the digits alternate: ababab... with a != b. |
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28
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| 101, 131, 151, 181, 191, 313, 353, 373, 383, 727, 757, 787, 797, 919, 929, 18181, 32323, 35353, 72727, 74747, 78787, 94949, 95959, 1212121, 1616161, 323232323, 383838383, 727272727, 919191919, 929292929, 979797979, 989898989
(list; graph; listen)
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OFFSET
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1,1
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REFERENCES
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C. A. Pickover, "Wonders of Numbers", Oxford New York 2001, Chapter 52, pp. 123-124, 316-317.
C. W. Trigg, Palindromic Octagonal Numbers, Journal of Recreational Mathematics, 15:1, pp. 41-46, 1982-83.
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LINKS
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P. De Geest, More undulating primes
R. Ondrejka, The Top Ten: a Catalogue of Primal Configurations
C. A. Pickover, "Wonders of Numbers, Adventures in Mathematics, Mind and Meaning," Zentralblatt review
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MAPLE
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for l from 3 to 31 by 2 do for i from 0 to 9 do for j from 0 to 9 do it1 := sum(i*10^(2*k), k=0..(l-1)/2): it2 := sum(j*10^(2*k+1), k=0..(l-3)/2): if isprime(it1+it2) and i<>j then printf(`%d, `, it1+it2) fi: od: od: od:
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CROSSREFS
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Cf. A032758.
Sequence in context: A089360 A056728 A085112 this_sequence A158089 A104946 A162463
Adjacent sequences: A059755 A059756 A059757 this_sequence A059759 A059760 A059761
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KEYWORD
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nonn,easy,base
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AUTHOR
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Jeffrey Heleen (meriaden(AT)hotmail.com), Feb 11 2001
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EXTENSIONS
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More terms and Maple code from James A. Sellers (sellersj(AT)math.psu.edu), Feb 13 2001
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