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 A144326 Prime numbers that cannot be Mersenne prime exponents, by conjecture of A144325. 1
 67, 191, 197, 211, 277, 331, 379, 397, 401, 541, 617, 631, 677, 727, 743, 751, 821, 937, 947, 971, 991, 1129, 1163, 1171, 1217, 1277, 1289, 1327, 1381, 1409, 1427, 1471, 1549, 1559, 1597, 1601, 1607, 1783, 1801, 1831, 1871, 1901, 2011, 2017, 2081, 2111 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Obviously true for the initial terms! Conjecture: 191, 1217, 1559 and 1901 are not in fact members of this sequence, noting that they are (4, 19) k-figurate numbers; 19 is a member of A138694. Determining whether a Mersenne prime exponent one greater than a (4, 19) k-figurate number exists is sufficient to determine whether these primes are members. LINKS CROSSREFS Cf. A000040, A000043, A000668, A144313, A144315, A144325, A138694 Sequence in context: A142544 A259888 A142671 * A119593 A142891 A142049 Adjacent sequences:  A144323 A144324 A144325 * A144327 A144328 A144329 KEYWORD easy,nonn AUTHOR Reikku Kulon, Sep 17 2008 STATUS approved

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Last modified December 16 14:52 EST 2018. Contains 318167 sequences. (Running on oeis4.)