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A065998
Concatenate n and number of divisors of n.
2
11, 22, 32, 43, 52, 64, 72, 84, 93, 104, 112, 126, 132, 144, 154, 165, 172, 186, 192, 206, 214, 224, 232, 248, 253, 264, 274, 286, 292, 308, 312, 326, 334, 344, 354, 369, 372, 384, 394, 408, 412, 428, 432, 446, 456, 464, 472, 4810, 493, 506, 514, 526, 532
OFFSET
1,1
LINKS
MATHEMATICA
cnd[n_]:=Module[{ds=DivisorSigma[0, n]}, n*10^IntegerLength[ds]+ds]; Array[ cnd, 60] (* Harvey P. Dale, Aug 22 2019 *)
PROG
(PARI) a(n) = fromdigits(concat(digits(n), digits(numdiv(n)))); \\ Michel Marcus, Apr 02 2017
CROSSREFS
Cf. A000005.
Sequence in context: A374365 A178897 A013576 * A364275 A351877 A073729
KEYWORD
nonn,base,changed
AUTHOR
Jeff Burch, Feb 28 2001
STATUS
approved