A220569 Smallest prime divisor of prime(n) + prime(n+1) + prime(n+2).
2, 3, 23, 31, 41, 7, 59, 71, 83, 97, 109, 11, 131, 11, 3, 173, 11, 199, 211, 223, 5, 251, 269, 7, 7, 311, 11, 7, 349, 7, 5, 11, 5, 439, 457, 3, 487, 503, 3, 13, 19, 5, 7, 19, 607, 3, 661, 7, 13, 701, 23, 17, 7, 3, 3, 11, 19, 829, 29, 857, 883, 911, 7, 941
Offset: 1
Keywords
Examples
a(6) = 7 because prime(6) + prime(6+1) + prime(6+2) = 13 + 17 + 19 = 49 and the smallest prime factor of 49 is 7.
Links
- Zak Seidov, Table of n, a(n) for n = 1..1000
Programs
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PARI
{a=2; b=3; c=5; for(n=1, 100, s=a+b+c; dv=divisors(s); print1(dv[2]", "); a=b; b=c; c=nextprime(c+2))}