OFFSET
1,1
COMMENTS
The smallest k such that 6*k+3 is the only abundant number among 6*k+1 through 6*k+5 is k = 157, with 6*k+3 = 945 = A005231(1).
The smallest k such that 6*k+1 is the only abundant number among 6*k+1 through 6*k+5 is k = 898568504, with 6*k+1 = 5391411025 = A115414(1).
The smallest k such that 6*k+5 is the only abundant number among 6*k+1 through 6*k+5 is k = 4492842520, with 6*k+5 = 26957055125 = A115414(2).
LINKS
Jianing Song, Table of n, a(n) for n = 1..10000
EXAMPLE
13 is a term since 80 is the only abundant number among 79, 80, 81, 82 and 83.
962 is not a term since there are 2 abundant numbers (5775 and 5776) among 5773, 5774, 5775, 5776 and 5777.
MATHEMATICA
q[n_] := Count[Range[5], _?(DivisorSigma[-1, 6*n + #] > 2 &)] == 1; Select[Range[0, 135], q] (* Amiram Eldar, Mar 21 2024 *)
PROG
(PARI) isA343306(k) = (sum(i=1, 5, sigma(6*k+i) > 2*(6*k+i)) == 1)
CROSSREFS
KEYWORD
nonn
AUTHOR
Jianing Song, Apr 11 2021
STATUS
approved