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A037279
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If n is composite, replace n by the concatenation of its proper divisors, otherwise a(n) = n.
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6
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1, 2, 3, 2, 5, 23, 7, 24, 3, 25, 11, 2346, 13, 27, 35, 248, 17, 2369, 19, 24510, 37, 211, 23, 2346812, 5, 213, 39, 24714, 29, 23561015, 31, 24816, 311, 217, 57, 234691218, 37, 219, 313, 24581020, 41, 23671421, 43, 241122, 35915, 223, 47, 23468121624, 7
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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EXAMPLE
| Divisors of 12 are 1,2,3,4,6,12, so a(12)=2346.
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MAPLE
| A037279 := proc(n) local dvs ; if isprime(n) or n = 1 then n; else dvs := [op(numtheory[divisors](n) minus {1, n} )] ; dvs := sort(dvs) ; cat(op(dvs)) ; fi ; end: seq(A037279(n), n=1..80) ; - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 23 2007
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CROSSREFS
| Cf. A037278, A120712, A106708.
Sequence in context: A120716 A084318 A084317 * A163591 A085307 A078599
Adjacent sequences: A037276 A037277 A037278 * A037280 A037281 A037282
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KEYWORD
| nonn,base
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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EXTENSIONS
| More terms from Erich Friedman (erich.friedman(AT)stetson.edu).
Edited by N. J. A. Sloane (njas(AT)research.att.com), Aug 29 2008 at the suggestion of R. J. Mathar
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