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A316097
Numbers n such that A(n+1) = A(n) + 6, where A() = A005101() are the abundant numbers.
2
1, 4, 5, 8, 9, 12, 15, 20, 27, 28, 29, 30, 33, 34, 37, 38, 41, 42, 49, 54, 55, 56, 57, 58, 61, 66, 67, 68, 73, 76, 77, 80, 84, 89, 92, 97, 98, 101, 102, 103, 108, 113, 116, 119, 122, 123, 126, 129, 134, 137, 142, 143, 144, 145, 152, 153, 160, 161, 162, 163
OFFSET
1,2
FORMULA
Sequence is { n | A005101(n+1) = A005101(n) + 6 }.
Sequence is { n | A125115(n) = 6 }.
MAPLE
with(numtheory): A:=select(n->sigma(n)>2*n, [$1..700]): a:=select(j->A[j+1]=A[j]+6, [$1..nops(A)-1]);
MATHEMATICA
Position[Map[{#1, #2 - 6} & @@ # &, Partition[Select[Range[10^3], DivisorSigma[1, #] > 2 # &], 2, 1]], _?(SameQ @@ # &)][[All, 1]] (* Michael De Vlieger, Jun 29 2018 *)
PROG
(GAP) A:=Filtered([1..700], n->Sigma(n)>2*n);; a:=Filtered([1..Length(A)-1], i->A[i+1]=A[i]+6);
CROSSREFS
A316099 is the main sequence for this entry.
Numbers n such that A(n+1) = A(n) + k, where A() = A005101() are the abundant numbers: A169822 (k=1), A303741 (k=2), A316095 (k=3), A316096 (k=4), this sequence (k=6).
Cf. A005101.
Sequence in context: A334992 A269984 A188085 * A206554 A267489 A073320
KEYWORD
nonn
AUTHOR
Muniru A Asiru, Jun 25 2018
STATUS
approved