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Search: id:A089176
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| A089176 |
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Primes p such that p+2 is divisible by a square. |
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+0
3
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| 2, 7, 23, 43, 47, 61, 73, 79, 97, 151, 167, 173, 223, 241, 277, 313, 331, 349, 359, 367, 373, 421, 439, 457, 523, 547, 601, 619, 673, 691, 709, 727, 733, 773, 823, 839, 853, 907, 929, 997, 1033, 1051, 1069, 1087, 1123, 1181, 1213, 1223, 1231, 1249, 1303
(list; graph; listen)
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OFFSET
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1,1
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PROGRAM
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(PARI) powerfreep3(n, p, k) = { c=0; pc=0; forprime(x=2, n, pc++; if(ispowerfree(x+k, p)==0, 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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A091880 gives prime indices.
Adjacent sequences: A089173 A089174 A089175 this_sequence A089177 A089178 A089179
Sequence in context: A049588 A106020 A045383 this_sequence A100917 A049552 A049572
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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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EXTENSIONS
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More terms from Ray Chandler (rayjchandler(AT)sbcglobal.net), Feb 15 2004
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