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A347250
Numbers k for which A331410(k) < A336361(k).
2
9, 17, 18, 34, 36, 49, 67, 68, 71, 72, 81, 97, 98, 134, 136, 142, 144, 147, 162, 193, 194, 196, 268, 271, 272, 283, 284, 288, 291, 293, 294, 324, 386, 388, 392, 536, 541, 542, 544, 566, 568, 576, 579, 582, 586, 587, 588, 647, 648, 679, 772, 776, 784, 961, 1072, 1082, 1084, 1087, 1088, 1132, 1136, 1151, 1152, 1158, 1163
OFFSET
1,1
COMMENTS
If k is a term, then also 2*k is present in this sequence.
PROG
(PARI)
A331410(n) = { my(f=factor(n)); sum(k=1, #f~, if(2==f[k, 1], 0, f[k, 2]*(1+A331410(f[k, 1]+1)))); };
A336361(n) = if(!bitand(n, n-1), 0, 1+A336361(sigma(n>>valuation(n, 2))));
A347249(n) = (A331410(n)-A336361(n));
isA347250(n) = (A347249(n)<0);
CROSSREFS
Positions of negative terms in A347249.
Sequence in context: A224442 A343111 A364540 * A192049 A133246 A190151
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 28 2021
STATUS
approved