A300098 -id:A300098 - cp's OEIS frontend

A300097 Primes for which A288814 gives a new record.

5, 7, 11, 17, 23, 29, 37, 53, 59, 67, 79, 89, 97, 127, 191, 211, 223, 307, 331, 479, 521, 541, 809, 877, 907, 1087, 1277, 1361, 1931, 2179, 2203, 2999, 3299, 4201, 4327, 4861, 5779, 7993, 8923, 12889, 14143, 15859, 16411, 16603, 18839, 19661, 24317, 25523, 28277

Offset: 1

Michel Marcus, Feb 24 2018

nonn

These are the primes that require the most effort when searching for the least composite c such that A001414(c) is a given prime, where A001414 is sopfr (sum of prime factors with repetition).
From David James Sycamore, Feb 25 2018: (Start)
Also primes for which A295185 gives a new record.
A006512 gives primes p requiring least effort, since then c=2*(p-2). (End)

Cf. A001414, A006512, A288814, A295185, A300098.

isok(k, n) = my(f=factor(k)); sum(j=1, #f~, f[j, 1]*f[j, 2]) == n;
scompo(n) = forcomposite(k=4, ,if (isok(k, n), return(k)));
lista(nn) = {my(last = 0); forprime(p=4, nn, my(val = scompo(p)); if (val > last, print1(p, ", "); last = val););}

cp's OEIS Frontend

A300097 Primes for which A288814 gives a new record.

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