A085585 Squares with exactly one odd digit.

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

Author

Zak Seidov, Jul 06 2003

Keywords

• nonn
• base

Comments

If k is a term, then so is 100*k. - Robert Israel, Sep 29 2023

Examples

			20164 is a term because 20164 = 142^2 and 20164 has exactly one odd digit.
		

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000290, A068690.

Programs

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
Select[Range[150]^2,Count[IntegerDigits[#],?OddQ]==1&] (* _Harvey P. Dale, Jul 27 2025 *)

Extensions

Name and example edited by Jon E. Schoenfield, Sep 29 2023