A139783 Quadruple lucky numbers (lower terms). Numbers n such that n, n+2, n+6, n+8 are all Lucky numbers.

1, 7, 67, 127, 613, 925, 1495, 1765, 2209, 2815, 3403, 5965, 6661, 8827, 9115, 15229, 16387, 18145, 19153, 21925, 23563, 24637, 27031, 27199, 28987, 31381, 32635, 34717, 35701, 36673, 40447, 43225, 43975, 47419, 50317, 51157, 56263, 64495

Offset

1,2

Comments

Weisstein comments: "the frequency of twin primes and twin lucky numbers are similar." This is to lucky numbers A000959 and A031158 Twin lucky numbers (lower terms) as prime numbers A000040 and A001359 Lesser of twin primes are to A007530 Prime quadruples: numbers n such that n, n+2, n+6, n+8 are all prime.

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Eric W. Weisstein, Lucky Number.

Formula

a(n) = {k such that k is in A000959 and k+2 is in A000959 and k+6 is in A000959 and k+8 is in A000959} = {k such that k is in A031158 and k+6 is in A031158}.

Example

a(1) = 1 because 1, 1+2=3, 1+6=7 and 1+8=9 are all lucky numbers A000959.
a(2) = 7 because 7, 7+2=9, 7+6=13 and 7+8=15 are all lucky numbers A000959.
a(3) = 67 because {67, 69, 73, 75} are all lucky numbers.
a(4) = 127 because {127, 129, 133, 135} are all lucky numbers.
a(5) = 613 because {613, 615, 619, 621} are all lucky numbers.
a(6) = 925 because {925, 927, 931, 933} are all lucky numbers.
a(7) = 1495 because {1495, 1497, 1501, 1503} are all lucky numbers.

Crossrefs

Cf. A000040, A000959, A001359, A031158.

Sequence in context: A261184 A384298 A142786 * A103102 A139910 A250227

Adjacent sequences: A139780 A139781 A139782 * A139784 A139785 A139786

Keyword

easy,nonn

Author

Jonathan Vos Post, May 20 2008

Extensions

Inserted a(8)=1765 and extended, R. J. Mathar, Jul 18 2008

Status

approved