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 A183076 Composite numbers of the form 2^k - 1 for which each prime divisor has the form 4j + 3. 8
 63, 1023, 16383, 32767, 67108863, 1073741823, 17179869183, 274877906943, 8796093022207, 2251799813685247, 4611686018427387903, 36893488147419103231 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Needed factorizations are in the Cunningham Project. LINKS Amiram Eldar, Table of n, a(n) for n = 1..39 S. S. Wagstaff, Jr., The Cunningham Project. FORMULA a(n) = 2^A183072(n) - 1. EXAMPLE 63 = 2^6 - 1 = 3^2 * 7, and 3 and 7 have the form 4j + 3. CROSSREFS Cf. A000668, A136005, A183075, A183077, A183078. Cf. A000043, A136003, A183071, A183072, A183073, A183074. Sequence in context: A112494 A258004 A258014 * A230660 A132465 A202983 Adjacent sequences: A183073 A183074 A183075 * A183077 A183078 A183079 KEYWORD nonn,hard AUTHOR Stuart Clary, Dec 23 2010 STATUS approved

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Last modified June 13 22:21 EDT 2024. Contains 373391 sequences. (Running on oeis4.)