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A104641
Numbers n such that n^3 has equal number of odd and even digits.
5
3, 12, 18, 19, 21, 47, 53, 54, 67, 68, 69, 72, 75, 76, 78, 84, 85, 87, 89, 93, 216, 224, 236, 238, 243, 245, 247, 249, 260, 262, 275, 297, 299, 301, 303, 308, 309, 310, 323, 325, 326, 332, 333, 343, 346, 355, 356, 362, 363, 371, 374, 378, 382, 383, 387, 388, 395, 396
OFFSET
1,1
LINKS
MATHEMATICA
EqedQ[n_]:= Module[{idn3 = IntegerDigits[n^3]}, Count[idn3, _?EvenQ] == Count[idn3, _?OddQ]]; Select[Range[2000], EqedQ] (* G. C. Greubel, Aug 14 2018 *)
PROG
(PARI) isok(n) = my(d = digits(n^3)); sum(i=1, #d, 1 - (d[i] % 2)) == sum(i=1, #d, d[i] % 2); \\ Michel Marcus, Oct 05 2013
CROSSREFS
Sequence in context: A354680 A047906 A342776 * A032703 A234904 A284806
KEYWORD
easy,nonn,base
AUTHOR
Zak Seidov, Mar 18 2005
STATUS
approved