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%I #8 Oct 03 2015 08:46:29
%S 0,1,4,169,324,1521,125316,126025,425104,1713481,1716100,4959529,
%T 24760576
%N a(n) = index of first n in A262680; positions of records in A262680.
%C All terms are squares (A262688 gives the square roots).
%C The even and odd terms alternate.
%o (PARI)
%o allocatemem((2^31)+(2^30));
%o uplim = 2^25;
%o v262680 = vector(uplim);
%o v262680[1] = 1; v262680[2] = 0;
%o for(i=3, uplim, v262680[i] = issquare(i) + v262680[i-numdiv(i)];
%o if(!(i%65536),print1(i,", ")););
%o A262680 = n -> if(!n,n,v262680[n]);
%o n=0; k=0; while(n*n <= uplim, if(A262680(n*n)==k, write("b262687.txt", k, " ", n*n); k++); n++;);
%o (Scheme, with _Antti Karttunen_'s IntSeq-library)
%o (define A262687 (RECORD-POS 0 0 A262680))
%Y Cf. A262680, A261088, A262514.
%Y Cf. A262688 (square roots of these terms).
%K nonn,more
%O 0,3
%A _Antti Karttunen_, Oct 03 2015
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