A152523
Multiplicities of distinct terms in A152522.
Original entry on oeis.org
1, 1, 1, 4, 1, 2, 4, 6, 6, 7, 6, 7, 4, 11, 3, 2, 5, 4, 1, 22, 11
Offset: 1
-
a152522(n) = my(P=prime(n)); forstep(k=6, 9e99, 2, forprime(p=3, P, if(isprime(k-p), next(2))); return(k));
lista(nn) = {my(last = a152522(1), newa, nb = 1); for (n=2, nn, newa = a152522(n); if (newa == last, nb++, print1(nb, ", "); last = newa; nb = 1););} \\ Michel Marcus, Dec 18 2018
A350713
Maximum smallest prime required to generate all Goldbach partitions to 10^n.
Original entry on oeis.org
3, 19, 73, 173, 293, 523, 751, 1093, 1789, 1877, 2803, 3457, 3917, 4909, 5569, 6961, 7753, 9341
Offset: 1
The first three partitions with the smallest first member are (3,3), (3,5), and (3,7), so the smallest prime required to generate all Goldbach partitions up through 10^1 is 3.
-
gp = Compile[{{n, Integer}}, Block[{p = 2}, While[! PrimeQ[n - p], p = NextPrime@p]; p]]; a[n] = 3; a[n] := Block[{k = 10^(n - 1), lmt = 10^n + 1, mx = 0}, While[k < lmt, b = gp@k; If[b > mx, mx = b]; k += 2]; mx]; (* Robert G. Wilson v, Mar 04 2022 *)
Comments