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A050626
Product of digits of n is a nonzero square.
6
1, 4, 9, 11, 14, 19, 22, 28, 33, 41, 44, 49, 55, 66, 77, 82, 88, 91, 94, 99, 111, 114, 119, 122, 128, 133, 141, 144, 149, 155, 166, 177, 182, 188, 191, 194, 199, 212, 218, 221, 224, 229, 236, 242, 248, 263, 281, 284, 289, 292, 298, 313, 326, 331, 334, 339, 343
OFFSET
1,2
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
MATHEMATICA
Select[Range[500], DigitCount[#, 10, 0]==0&&IntegerQ[Sqrt[Times@@ IntegerDigits[ #]]]&] (* Harvey P. Dale, Jun 09 2020 *)
PROG
(Magma) [ n: n in [1..350] | s gt 0 and IsSquare(s) where s is &*Intseq(n, 10) ]; // Bruno Berselli, May 26 2011
(PARI) is(n)=my(v=digits(n), pr=prod(i=1, #v, v[i])); pr&&issquare(pr) \\ Charles R Greathouse IV, May 19 2013
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Jun 15 1999
STATUS
approved