login
A030158
Even squares in which parity of digits alternates.
5
0, 4, 16, 36, 256, 676, 1296, 5476, 7056, 9216, 41616, 69696, 87616, 147456, 163216, 181476, 329476, 341056, 367236, 527076, 541696, 583696, 763876, 781456, 929296, 2143296, 2509056, 2547216, 2903616, 4145296, 4301476
OFFSET
1,2
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..10000 (First 359 terms from Vincenzo Librandi)
FORMULA
a(n) = A030157(n)^2. - Michel Marcus, Aug 15 2018
MATHEMATICA
Join[{0, 4}, id[n_]:=IntegerDigits[n^2]; t={}; Do[If[Length[id[n]]==1, AppendTo[t, n], If[Union[Abs[Differences[Boole/@EvenQ[id[n]]]]]=={1}, AppendTo[t, n^2]]], {n, 4, 6000, 2}]; t] (* Vincenzo Librandi, Aug 15 2018 *)
CROSSREFS
Cf. A030157.
Sequence in context: A263385 A368215 A130279 * A054246 A173545 A340233
KEYWORD
nonn,base
EXTENSIONS
Offset changed by Michel Marcus, Aug 15 2018
STATUS
approved