A055727 Number of lucky 4,6 triples <= 10^n.

0, 2, 4, 14, 51, 247, 1405, 8506, 55228

Offset

0,2

Comments

A lucky 4,6 triple is a triple (k, k+4, k+6) such that k, k+4, and k+6 are lucky numbers and no other number between k and k+6 is lucky. - Sean A. Irvine, Apr 04 2022

A triple is counted in a(n) if its smallest member is at most 10^n. - Pontus von Brömssen, Apr 04 2022

Links

Table of n, a(n) for n=0..8.

Crossrefs

Cf. A000959.

Sequence in context: A092665 A046650 A327235 * A003500 A316363 A295760

Adjacent sequences: A055724 A055725 A055726 * A055728 A055729 A055730

Keyword

nonn,less,more

Author

Robert G. Wilson v, Jun 09 2000

Extensions

a(7) from Sean A. Irvine, Apr 04 2022

a(8) from Pontus von Brömssen, Apr 04 2022

Status

approved