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A361262
Numbers k such that k+i^2, i=0..6 are all semiprimes.
0
3238, 4162, 4537, 13918, 16837, 17857, 18673, 24553, 55477, 62353, 78457, 84358, 92878, 102838, 106813, 129838, 135853, 140002, 142822, 146722, 148318, 151957, 166177, 180013, 184213, 187933, 194338, 210637, 214393, 231757, 242698, 271198, 274393, 305677
OFFSET
1,1
EXAMPLE
3238 is a term because 3238=2*1619; 3239=41*79; 3242=2*1621; 3247=17*191; 3254=2*1627; 3263=13*251; 3274=2*1637.
MAPLE
q:= n-> andmap(x-> numtheory[bigomega](x)=2, [n+i^2$i=0..6]):
select(q, [$1..400000])[]; # Alois P. Heinz, Mar 06 2023
PROG
(PARI) isok(k) = sum(i=0, 6, bigomega(k+i^2)==2) == 7;
CROSSREFS
Subsequence of A070552.
Cf. A001358 (semiprimes).
Sequence in context: A283578 A231141 A252611 * A185465 A371949 A254974
KEYWORD
nonn
AUTHOR
Alexandru Petrescu, Mar 06 2023
STATUS
approved