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Search: id:A089202
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| A089202 |
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Primes p such that p-2 and p+2 are divisible by a cube. |
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+0
1
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| 4457, 10987, 15377, 20873, 32587, 39877, 51109, 53377, 54623, 60127, 66877, 74873, 101873, 107377, 112997, 115589, 120877, 121123, 125197, 126443, 128873, 135623, 143719, 148957, 155377, 161053, 161377, 162623, 168127, 169373, 174877, 176123
(list; graph; listen)
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OFFSET
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1,1
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EXAMPLE
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4457-2 = 3^4*5*11,4457+2 = 7^3*13
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PROGRAM
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(PARI) powerfreep4(n, p, k) = { c=0; pc=0; forprime(x=2, n, pc++; if(!ispowerfree(x-k, p) && !ispowerfree(x+k, p), c++; print1(x", "); ) ); print(); print(c", "pc", "c/pc+.0) } ispowerfree(m, p1) = { flag=1; y=component(factor(m), 2); for(i=1, length(y), if(y[i] >= p1, flag=0; break); ); return(flag) }
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CROSSREFS
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Sequence in context: A043508 A114908 A102622 this_sequence A139068 A031655 A031565
Adjacent sequences: A089199 A089200 A089201 this_sequence A089203 A089204 A089205
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KEYWORD
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easy,nonn
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AUTHOR
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Cino Hilliard (hillcino368(AT)gmail.com), Dec 08 2003
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