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A337385 Odd numbers k for which A003973(k) >= 2*A003961(k). 1
334639305, 1003917915, 1265809545, 1353106755, 1673196525, 2109682575, 2255177925, 2342475135, 2553826275, 2691663975, 2729952225, 2953555605, 2982654675, 3011753745, 3128150025, 3157249095, 3234846615, 3258330075, 3419140725, 3442113675, 3681032355, 3797428635, 3855626775, 4059320265, 4292112825, 4350310965 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Provided that there are no odd perfect numbers, then applying A003961 to each term and sorting into ascending order gives A115414.
Apparently, all terms are divisible by 255255 = 3*5*7*11*13*17. - Hugo Pfoertner, Sep 24 2020
LINKS
PROG
(PARI)
A003961(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
isA337385(n) = if(!(n%2), 0, my(x=A003961(n)); (sigma(x)>=2*x));
CROSSREFS
Subsequence of A337386.
Sequence in context: A222978 A353541 A271112 * A233703 A230085 A204337
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 31 2020
STATUS
approved

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Last modified March 19 07:04 EDT 2024. Contains 370953 sequences. (Running on oeis4.)