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 A057777 a(n) is the smallest number such that a(n)+1 is a prime and the largest power of 2 which divides it is 2^n. 1
 1, 2, 4, 40, 16, 96, 192, 640, 256, 7680, 13312, 18432, 12288, 40960, 114688, 163840, 65536, 1179648, 786432, 5767168, 7340032, 23068672, 104857600, 377487360, 754974720, 167772160, 469762048, 2013265920, 3489660928, 12348030976 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS EXAMPLE The 4th term is 40. It is divisible by 8,40+1=41 is prime. Smaller multiples of 8 are not suitable because e.g. albeit 8|16 and 16+1=17 is a prime, but the largest power of 2 which divides 16 is not 8, it is 16. So 16 is not the 3rd, it is the 4th term here. CROSSREFS Sequence in context: A106127 A018992 A098625 * A139735 A184952 A098337 Adjacent sequences:  A057774 A057775 A057776 * A057778 A057779 A057780 KEYWORD nonn AUTHOR Labos Elemer, Nov 02 2000 EXTENSIONS More terms from Larry Reeves (larryr(AT)acm.org), Nov 03 2000 STATUS approved

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Last modified August 3 07:58 EDT 2021. Contains 346435 sequences. (Running on oeis4.)