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A109958
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Concatenate n and the sum of primes dividing n (counting multiplicity).
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2
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10, 22, 33, 44, 55, 65, 77, 86, 96, 107, 1111, 127, 1313, 149, 158, 168, 1717, 188, 1919, 209, 2110, 2213, 2323, 249, 2510, 2615, 279, 2811, 2929, 3010, 3131, 3210, 3314, 3419, 3512, 3610, 3737, 3821, 3916, 4011, 4141, 4212, 4343, 4415, 4511, 4625, 4747
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OFFSET
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1,1
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LINKS
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FORMULA
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MAPLE
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f:= proc(n) local q;
q:= add(t[1]*t[2], t=ifactors(n)[2]);
10^(1+ilog10(q))*n+q
end proc:
f(1):= 10:
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MATHEMATICA
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pr[{a_, b_}]:=a*b; Join[{10}, Table[FromDigits[Flatten[IntegerDigits[Join[{n}, {Total[pr/@FactorInteger[n]]}]]]], {n, 2, 47}]] (* James C. McMahon, Apr 02 2024 *)
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CROSSREFS
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KEYWORD
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easy,nonn,base
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AUTHOR
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STATUS
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approved
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