OFFSET
0,2
LINKS
Donovan Johnson, Table of n, a(n) for n = 0..1000
EXAMPLE
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).
a(1) = 4 = 4 + 0; a(2) = 13 = 4 + 9 = 9 + 4; a(3) = 10 = 6 + 4
= 9 + 1 = 10 + 0.
PROG
(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 */
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post and Ray Chandler, Dec 14 2004
STATUS
approved