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URL: https://oeis.org/A385858

⇱ A385858 - OEIS

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A385858
Numbers m in A385402 which are not prime.
0
1, 35, 77, 95, 119, 125, 143, 187, 209, 221, 247, 259, 299, 319, 323, 377, 391, 403, 427, 437, 473, 493, 527, 551, 589, 629, 667, 697, 713, 731, 779, 799, 817, 851, 893, 899, 943, 989, 1007, 1073, 1139, 1147, 1189, 1199, 1219, 1247, 1271, 1313, 1333, 1343, 1357, 1363, 1387, 1397
OFFSET
1,2
COMMENTS
Since all the primes are in A385402, this sequence is more concise.
MATHEMATICA
fQ[m_] := Sum[ GCD[m, Floor[m/k]], {k, m}] == Sum[ GCD[m, Ceiling[m/k]], {k, m}]; j = 1; lst = {}; While[j < 1400, If[ !PrimeQ@ j && fQ@ j, AppendTo[lst, j]]; j++]; lst
PROG
(PARI) isok(m) = if (!isprime(m), sum(k=1, m, gcd(m, floor(m/k))) == sum(k=1, m, gcd(m, ceil(m/k)))); \\ Michel Marcus, Jul 10 2025
CROSSREFS
Proper subset of A385402.
Sequence in context: A043985 A254443 A300160 * A257750 A257751 A259282
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Jul 10 2025
STATUS
approved