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%I #8 Feb 04 2013 22:27:44
%S 1,4,13,10,26,50,58,74,146,159,218,302,290,458,515,647,650,794,962,
%T 986,1178,1403,1322,1418,1658,1898,1802,2126,1970,2210,3062,2930,3143,
%U 3263,3482,3527,4142,4667,4010,4562,5123,4955,5018,6242,5330,6695,7178,7103
%N Least positive integer that can be represented as sum of a semiprime and a square in exactly n ways.
%H Donovan Johnson, <a href="/A101181/b101181.txt">Table of n, a(n) for n = 0..1000</a>
%F a(n) = min(i such that i = A001358(j) + A000290(k) in n ways).
%e a(0) = 1 because 1 is the smallest positive integer that cannot be represented as sum of a semiprime and a square (since 4 is the smallest semiprime).
%e a(1) = 4 = 4 + 0; a(2) = 13 = 4 + 9 = 9 + 4; a(3) = 10 = 6 + 4
%e = 9 + 1 = 10 + 0.
%o (PARI) mx=4345802; v=vector(mx); sp=vector(856467); c=0; for(i=4, mx, if(bigomega(i)==2, c++; sp[c]=i)); for(i=0, 2084, sq=i^2; for(j=1, c, s=sq+sp[j]; if(s<=mx, v[s]++, next(2)))); n=vector(1049); for(i=4, mx, if(v[i]>0, if(n[v[i]]==0, n[v[i]]=i))); for(i=1, 1000, write("b101181.txt", i " " n[i])) /* _Donovan Johnson_, Feb 04 2013 */
%Y Cf. A000290, A001358, A100570.
%K easy,nonn
%O 0,2
%A _Jonathan Vos Post_ and _Ray Chandler_, Dec 14 2004
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