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%I #32 Jul 27 2021 15:47:11
%S 0,0,0,2,0,23,0,24,3,25,0,2346,0,27,35,248,0,2369,0,24510,37,211,0,
%T 2346812,5,213,39,24714,0,23561015,0,24816,311,217,57,234691218,0,219,
%U 313,24581020,0,23671421,0,241122,35915,223,0,23468121624,7,251025,317
%N a(n) is the concatenation of its nontrivial divisors.
%H Klaus Brockhaus, <a href="/A106708/b106708.txt">Table of n, a(n) for n=1..5000</a>
%F a(n) = A037279(n) * A010051(n). - _R. J. Mathar_, Aug 01 2007
%p A106708 := proc(n) local dvs ; if isprime(n) or n = 1 then 0; else dvs := [op(numtheory[divisors](n) minus {1,n} )] ; dvs := sort(dvs) ; cat(op(dvs)) ; fi ; end: seq(A106708(n),n=1..80) ; # _R. J. Mathar_, Aug 01 2007
%t Table[If[CompositeQ[n],FromDigits[Flatten[IntegerDigits/@Rest[ Most[ Divisors[ n]]]]],0],{n,60}] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jun 22 2020 *)
%o (PARI)
%o {map(n) = local(d); d=divisors(n); if(#d<3, 0, d[1]=""; eval(concat(vecextract(d, concat("..", #d-1)))))}
%o for(n=1,51,print1(map(n),",")) /* _Klaus Brockhaus_, Aug 05 2007 */
%o (Haskell)
%o a106708 1 = 0
%o a106708 n
%o | a010051 n == 1 = 0
%o | otherwise = read $ concat $ (map show) $ init $ tail $ a027750_row n
%o -- _Reinhard Zumkeller_, May 01 2012
%o (Python)
%o from sympy import divisors
%o def a(n):
%o nontrivial_divisors = [d for d in divisors(n)[1:-1]]
%o if len(nontrivial_divisors) == 0: return 0
%o else: return int("".join(str(d) for d in nontrivial_divisors))
%o print([a(n) for n in range(1, 52)]) # _Michael S. Branicky_, Dec 31 2020
%Y Cf. A037278, A120712, A037279, A131983 (records), A131984 (where records occur).
%Y Cf. A027750, A010051, A037285, A037277, A163870.
%K nonn,base
%O 1,4
%A _N. J. A. Sloane_, Jul 20 2007
%E More terms from _R. J. Mathar_ and _Klaus Brockhaus_, Aug 01 2007
%E Name edited by _Michael S. Branicky_, Dec 31 2020
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