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A052213
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Numbers n with prime signature(n) = prime signature(n+1).
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3
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2, 14, 21, 33, 34, 38, 44, 57, 75, 85, 86, 93, 94, 98, 116, 118, 122, 133, 135, 141, 142, 145, 147, 158, 171, 177, 201, 202, 205, 213, 214, 217, 218, 230, 244, 253, 285, 296, 298, 301, 302, 326, 332, 334, 375, 381, 387, 393, 394, 429, 434, 445, 446, 453, 481
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| pri[ n_ ] := Sort[ Transpose[ FactorInteger[ n ] ][ [ 2 ] ] ] Select[ Range[ 2,1000 ],pri[ # ]==pri[ #+1 ]& ]
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LINKS
| T. D. Noe, Table of n, a(n) for n=1..10000
MathOverflow, Question on consecutive integers with similar prime factorizations [From T. D. Noe (noe(AT)sspectra.com), Jul 19 2010]
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EXAMPLE
| 14 = 2^1 7^1 and 15 = 3^1 5^1, so both have prime signature {1,1}.
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CROSSREFS
| Sequence in context: A138047 A005237 A140578 * A086263 A073143 A066613
Adjacent sequences: A052210 A052211 A052212 * A052214 A052215 A052216
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KEYWORD
| easy,nonn
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AUTHOR
| Erich Friedman (efriedma(AT)stetson.edu), Jan 29 2000
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