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 A106708 a(n) is the concatenation of its nontrivial divisors. 10
 0, 0, 0, 2, 0, 23, 0, 24, 3, 25, 0, 2346, 0, 27, 35, 248, 0, 2369, 0, 24510, 37, 211, 0, 2346812, 5, 213, 39, 24714, 0, 23561015, 0, 24816, 311, 217, 57, 234691218, 0, 219, 313, 24581020, 0, 23671421, 0, 241122, 35915, 223, 0, 23468121624, 7, 251025, 317 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 LINKS Klaus Brockhaus, Table of n, a(n) for n=1..5000 FORMULA a(n) = A037279(n) * A010051(n). - R. J. Mathar, Aug 01 2007 MAPLE 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 MATHEMATICA 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 *) PROG (PARI) {map(n) = local(d); d=divisors(n); if(#d<3, 0, d[1]=""; eval(concat(vecextract(d, concat("..", #d-1)))))} for(n=1, 51, print1(map(n), ", ")) /* Klaus Brockhaus, Aug 05 2007 */ (Haskell) a106708 1           = 0 a106708 n    | a010051 n == 1 = 0    | otherwise = read \$ concat \$ (map show) \$ init \$ tail \$ a027750_row n -- Reinhard Zumkeller, May 01 2012 (Python) from sympy import divisors def a(n):   nontrivial_divisors = [d for d in divisors(n)[1:-1]]   if len(nontrivial_divisors) == 0: return 0   else: return int("".join(str(d) for d in nontrivial_divisors)) print([a(n) for n in range(1, 52)]) # Michael S. Branicky, Dec 31 2020 CROSSREFS Cf. A037278, A120712, A037279, A131983 (records), A131984 (where records occur). Cf. A027750, A010051, A037285, A037277, A163870. Sequence in context: A293938 A254042 A009378 * A138551 A133490 A051728 Adjacent sequences:  A106705 A106706 A106707 * A106709 A106710 A106711 KEYWORD nonn,base AUTHOR N. J. A. Sloane, Jul 20 2007 EXTENSIONS More terms from R. J. Mathar and Klaus Brockhaus, Aug 01 2007 Name edited by Michael S. Branicky, Dec 31 2020 STATUS approved

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Last modified July 4 10:11 EDT 2022. Contains 355075 sequences. (Running on oeis4.)