A125689 Smallest number having exactly n partitions into three distinct primes.

1, 10, 18, 26, 31, 35, 39, 80, 49, 47, 57, 53, 63, 59, 65, 67, 248, 73, 71, 79, 85, 77, 93, 105, 332, 83, 89, 111, 97, 482, 95, 103, 101, 674, 135, 129, 115, 107, 800, 113, 1040, 121, 1010, 119, 127, 125, 153, 159, 133, 1136, 145, 131, 171, 1304, 137, 151, 1520

Offset

0,2

Comments

A125688(a(n)) = n and A125688(m) <> n for m < a(n).

Links

Andrew Howroyd, Table of n, a(n) for n = 0..1000

Prog

(PARI) \\ here b(n) is A125688.
b(n, brk=oo)={my(s=0); forprime(p=2, n\3, if((n-p)%2==0, forprime(q=p+1, (n-p)/2-1, if(isprime(n-p-q), s++; if(s>=brk, return(-1))) ))); s}
sols(n, lim, f)={my(u=vector(n), r=n); for(i=1, lim, my(t=f(i)); if(t>0 && t<=#u && !u[t], u[t]=i; r--; if(r==0, return(u)))); my(m=1); while(m<=#u && u[m], m++); u[1..m-1]}
{ my(nn=100); nn++; sols(nn, 10^4, i->b(i, nn)+1) } \\ Andrew Howroyd, Jan 06 2020

Crossrefs

Cf. A125688.

Sequence in context: A245578 A165250 A257512 * A244573 A230356 A100992

Adjacent sequences: A125686 A125687 A125688 * A125690 A125691 A125692

Keyword

nonn

Author

Reinhard Zumkeller, Nov 30 2006

Extensions

Terms a(40) and beyond from Andrew Howroyd, Jan 06 2020

Status

approved