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A089203
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Primes p such that p-2 and p+2 are divisible by a fourth power.
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0
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169373, 371873, 574373, 741877, 843127, 979373, 1146877, 1615871, 1688123, 1754377, 1789373, 1855627, 2004833, 2093123, 2260627, 2498123, 2665627, 2700623, 2782757, 2903123, 3206873, 3374377, 3510623, 3560681, 3611873
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| 169373 - 2 = 3^5*17*41, 169373 + 2 = 5^4*271
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PROG
| (PARI) \Input no. of iterations n, power p and number to subtract and add k. 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
| Sequence in context: A156427 A185474 A034211 * A116890 A126894 A206059
Adjacent sequences: A089200 A089201 A089202 * A089204 A089205 A089206
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KEYWORD
| easy,nonn
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AUTHOR
| Cino Hilliard (hillcino368(AT)gmail.com), Dec 08 2003
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