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 A030152 Squares in which parity of digits alternates. 24
 0, 1, 4, 9, 16, 25, 36, 49, 81, 121, 169, 256, 361, 529, 676, 729, 961, 1296, 4761, 5476, 6561, 7056, 9216, 12321, 12769, 14161, 16129, 18769, 32761, 34969, 41616, 56169, 69696, 72361, 74529, 76729, 78961, 87616, 96721, 147456, 163216, 181476, 212521 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Giovanni Resta, Table of n, a(n) for n = 1..10000 (first 1000 terms from Reinhard Zumkeller) FORMULA A010052(a(n)) * A228710(a(n)) = 1. - Reinhard Zumkeller, Aug 31 2013 EXAMPLE 1296 is a term as 1, 2, 9 and 6 have odd and even parity alternately. MAPLE i := 0:for a from 1 to 1000 do b := a^2:g := ceil(log(b+1)/log(10)):iss := true:for j from 1 to g-1 do if((b mod 2)=1) then if((floor(b/10^j) mod 2)=((-1)^(j+1)+1)/2) then iss := false:end if:else if((floor(b/10^j) mod 2)=((-1)^j+1)/2) then iss := false:end if:end if:end do: if(iss=true) then i := i+1:c[i] := b:end if:end do:q := seq(c[k], k=1..i-1); # Sascha Kurz, Mar 23 2002 MATHEMATICA altQ[n_] := n < 10 || Union[Total /@ Partition[ Mod[ IntegerDigits@n, 2], 2, 1]] == {1}; Select[ Range[0, 500]^2, altQ[#] &] (* Giovanni Resta, Aug 16 2018 *) PROG (Haskell) a030152 n = a030152_list !! (n-1) a030152_list = filter ((== 1) . a228710) a000290_list -- Reinhard Zumkeller, Aug 31 2013 CROSSREFS Cf. A030142, A030143, A030144, A030152, A030153, A030154, A030159. Intersection of A000290 and A030141. Sequence in context: A084617 A179126 A068879 * A030288 A030154 A122541 Adjacent sequences:  A030149 A030150 A030151 * A030153 A030154 A030155 KEYWORD nonn,base AUTHOR EXTENSIONS Edited by N. J. A. Sloane, Aug 31 2009 at the suggestion of R. J. Mathar Offset corrected by Reinhard Zumkeller, Aug 31 2013 STATUS approved

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Last modified July 21 04:40 EDT 2019. Contains 325189 sequences. (Running on oeis4.)