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A235717 Squares which have one or more occurrences of exactly two different digits. 11
16, 25, 36, 49, 64, 81, 100, 121, 144, 225, 400, 441, 484, 676, 900, 1444, 7744, 10000, 11881, 29929, 40000, 44944, 55225, 69696, 90000, 1000000, 4000000, 9000000, 9696996, 100000000, 400000000, 900000000, 6661661161, 10000000000, 40000000000, 90000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The first term having a repeated digit is 100.
This sequence is the same as A018885, except that A018885 has four additional leading terms.
LINKS
FORMULA
a(n) = A016069(n)^2.
EXAMPLE
69696 is in the sequence because 69696 = 264^2 and 69696 contains exactly two different digits: 6 and 9.
PROG
(PARI) s=[]; for(n=1, 10000, if(#vecsort(eval(Vec(Str(n^2))), , 8)==2, s=concat(s, n^2))); s
CROSSREFS
Sequence in context: A001033 A100647 A245371 * A368049 A319388 A291334
KEYWORD
nonn,base
AUTHOR
Colin Barker, Jan 15 2014
STATUS
approved

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Last modified March 29 06:57 EDT 2024. Contains 371265 sequences. (Running on oeis4.)