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A083525
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a(1) = 1, a(n) = a(n-1)*n if n is composite, a(n) = a(n-1) + n if n is a prime.
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2
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1, 3, 6, 24, 29, 174, 181, 1448, 13032, 130320, 130331, 1563972, 1563985, 21895790, 328436850, 5254989600, 5254989617, 94589813106, 94589813125, 1891796262500, 39727721512500, 874009873275000, 874009873275023, 20976236958600552
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OFFSET
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1,2
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LINKS
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MAPLE
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a := proc(n) option remember: if n=1 then RETURN(1) fi: if isprime(n) then RETURN(a(n-1)+n) else RETURN(a(n-1)*n) fi: end: for n from 1 to 50 do printf(`%d, `, a(n)) od: # James A. Sellers, May 19 2003
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MATHEMATICA
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nxt[{a_, n_}]:={If[PrimeQ[n+1], a+n+1, a(n+1)], n+1}; Transpose[ NestList[ nxt, {1, 1}, 30]][[1]] (* Harvey P. Dale, Jun 24 2014 *)
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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