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A139783 Quadruple lucky numbers (lower terms). Numbers n such that n, n+2, n+6, n+8 are all Lucky numbers. 1
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 (list; graph; refs; listen; history; text; internal format)
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
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
Sequence in context: A106111 A261184 A142786 * A103102 A139910 A250227
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

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)