A108926 Initial members of abundant quintuplets, i.e., values of k such that (k, k+2, k+4, k+6, k+8) are all abundant numbers.
2988, 4728, 9724, 18844, 22984, 30544, 35148, 39948, 45048, 50464, 55788, 56808, 58056, 58780, 69184, 78048, 81948, 85744, 101148, 106144, 108256, 109248, 117124, 134088, 139744, 139804, 152568, 171288, 174348, 175908, 182644, 189768, 197028
Offset: 1
Keywords
Links
- Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..5000 from Shyam Sunder Gupta)
Programs
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Mathematica
SequencePosition[Table[If[DivisorSigma[1,n]>2n,1,0],{n,200000}],{1,,1,,1,,1,,1}][[All,1]] (* Harvey P. Dale, Mar 06 2022 *) -
PARI
is(n)=sigma(n,-1)>2 && sigma(n+2,-1)>2 && sigma(n+4,-1)>2 && sigma(n+6,-1)>2 && sigma(n+8,-1)>2 \\ Charles R Greathouse IV, Feb 21 2017