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 A037278 Replace n with concatenation of its divisors. 56
 1, 12, 13, 124, 15, 1236, 17, 1248, 139, 12510, 111, 1234612, 113, 12714, 13515, 124816, 117, 1236918, 119, 12451020, 13721, 121122, 123, 1234681224, 1525, 121326, 13927, 12471428, 129, 12356101530, 131, 12481632, 131133, 121734, 15735, 123469121836, 137 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) is the union of A176555(n) for n >= 1 and A176556(n) for n >= 2. See A176553 (numbers m such that concatenations of divisors of m are noncomposites) and A176554 (numbers m such that concatenations of divisors of m are nonprimes). [Jaroslav Krizek, Apr 21 2010] a(n) is the concatenation of n-th row of the triangle in A027750. LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 MAPLE a:=n->parse(cat(op(sort([op(divisors(n))])))): seq(a(n), n=1..34); # Paolo P. Lava, Mar 29 2018 MATHEMATICA a[n_] := ToExpression[ StringJoin[ ToString /@ Divisors[n] ] ]; Table[ a[n], {n, 1, 34}] (* Jean-François Alcover, Dec 01 2011 *) FromDigits[Flatten[IntegerDigits/@Divisors[#]]]&/@Range[40] (* Harvey P. Dale, Nov 09 2012 *) PROG (Haskell) a037278 = read . concatMap show . a027750_row :: Integer -> Integer -- Reinhard Zumkeller, Jul 13 2013, May 01 2012, Aug 07 2011 (PARI) a(n) = my(s=""); fordiv(n, d, s = concat(s, Str(d))); eval(s); \\ Michel Marcus, Jun 01 2019 and Sep 22 2022 (Magma) k:=1; sol:=[]; for u in [1..34] do D:=Divisors(u); conc:=D[1]; for u1 in [2..#D] do a:=#Intseq(conc); a1:=#Intseq(D[u1]); conc:=10^a1*conc+D[u1]; end for; sol[u]:=conc; k:=k+1; end for; sol; // Marius A. Burtea, Jun 01 2019 (MATLAB) m=1; for u=1:34 div=divisors(u); conc=str2num(strrep(num2str(div), ' ', '')); sol(m)=conc; m=m+1; end sol % Marius A. Burtea, Jun 01 2019 (Python) from sympy import divisors def a(n): return int("".join(str(d) for d in divisors(n))) print([a(n) for n in range(1, 35)]) # Michael S. Branicky, Dec 31 2020 CROSSREFS Cf. A027750, A037283, A037277, A106708. Sequence in context: A135123 A129476 A243361 * A164852 A362113 A033048 Adjacent sequences: A037275 A037276 A037277 * A037279 A037280 A037281 KEYWORD nonn,easy,base,nice AUTHOR N. J. A. Sloane EXTENSIONS More terms from Erich Friedman STATUS approved

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Last modified June 7 11:47 EDT 2023. Contains 363157 sequences. (Running on oeis4.)