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A101320
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Numbers n such that 4n-1, 8n-1, 16n-1, 32n-1, 64n-1 and 128n-1 are primes.
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2
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15855, 31785, 267300, 280665, 399675, 561330, 946050, 990510, 1022220, 1082115, 1164735, 1283250, 1303875, 1309545, 1514880, 1669065, 1924410, 2850225, 3078675, 3092760, 3492270, 3536385, 3611205, 3920670, 4148970, 4454775
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OFFSET
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1,1
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LINKS
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EXAMPLE
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4*15855-1, 8*15855-1, 16*15855-1, 32*15855-1, 64*15855-1 and 128*15855-1 are primes, so 15855 is a term.
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PROG
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(PARI) lista(nn) = for(n=15855, nn, if(ispseudoprime(4*n-1) && ispseudoprime(8*n-1) && ispseudoprime(16*n-1) && ispseudoprime(32*n-1) && ispseudoprime(64*n-1) && ispseudoprime(128*n-1), print1(n, ", "))) \\ Iain Fox, Nov 23 2017
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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Douglas Stones (dssto1(AT)student.monash.edu.au), Dec 23 2004
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STATUS
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approved
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