A229544 Numbers k such that k*product_of_digits(k) is a nonzero cube.
1, 8, 243, 784, 7776, 9826, 13122, 24389, 26244, 39366, 47628, 55566, 59895, 71442, 82944, 122825, 124416, 226981, 263424, 275625, 316368, 323433, 333396, 588245, 663255, 774144, 843648, 1339893, 1492992, 1613472, 2341344, 3816336, 3981312, 8719893, 8992364, 9393931, 9927988, 11212884, 11239424, 14823774
Offset: 1
Examples
7776*(7*7*7*6) = 1600030008 = 252^3. Thus, 7776 is a member of this sequence.
Programs
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PARI
isok(k) = my(p=vecprod(digits(k))); p && ispower(k*p, 3); \\ Michel Marcus, Aug 24 2025
Extensions
Corrected and extended by Derek Orr, Mar 22 2015