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A085585
Squares with exactly one odd digit.
2
1, 9, 16, 25, 36, 49, 81, 100, 144, 225, 256, 289, 324, 441, 625, 676, 784, 841, 900, 1024, 1444, 1600, 2025, 2209, 2304, 2401, 2500, 2601, 2704, 2809, 3600, 3844, 4096, 4225, 4489, 4900, 6241, 6724, 6889, 8100, 8281, 8649, 8836, 9604, 10000, 10404
OFFSET
1,2
COMMENTS
If k is a term, then so is 100*k. - Robert Israel, Sep 29 2023
LINKS
EXAMPLE
20164 is a term because 20164 = 142^2 and 20164 has exactly one odd digit.
MAPLE
filter:= proc(n) nops(select(type, convert(n, base, 10), even))=1 end proc:
select(filter, [seq(i^2, i=1..10000)]); # Robert Israel, Sep 29 2023
MATHEMATICA
bb={}; Do[idp=IntegerDigits[n^2]; len=Length[idp]; If[Sum[Mod[idp[[i]], 2], {i, len}]==1, bb={bb, n}], {n, 200}]; Flatten[bb]^2
CROSSREFS
Sequence in context: A227650 A339859 A076093 * A026062 A108945 A177430
KEYWORD
nonn,base
AUTHOR
Zak Seidov, Jul 06 2003
EXTENSIONS
Name and example edited by Jon E. Schoenfield, Sep 29 2023
STATUS
approved