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A074328
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Numbers m such that prime(m^2+1)-prime(m^2)=2, where prime(j) is the j-th prime.
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0
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7, 8, 9, 12, 15, 16, 22, 25, 27, 34, 53, 83, 85, 88, 95, 107, 108, 144, 149, 187, 196, 223, 234, 238, 249, 255, 268, 274, 315, 324, 350, 355, 358, 367, 386, 410, 411, 416, 424, 436, 440, 445, 450, 462, 469, 471, 481, 494, 501, 509, 511, 517, 522, 549, 554, 564
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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25 is here because 626th and 625th primes are twin: 4639-4637=2.
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MATHEMATICA
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t=Table[0, {250}]; t1=Table[0, {250}]; s=0; k=0; Do[s=Prime[1+n^2]-Prime[n^2]; If[s==2, k=k+1; t[[k]]=n; t1[[k]]=Prime[n^2]; Print[{k, n, Prime[n^2]}]], {n, 1, 2500}] t t1
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PROG
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(PARI) isok(m) = my(p=prime(m^2)); nextprime(p+1) - p == 2; \\ Michel Marcus, Oct 20 2022
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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