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Search: id:A118873
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| A118873 |
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Determinant of n-th continuous block of 4 consecutive squares of primes. |
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+0
1
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| -29, -136, -1704, -6288, -5160, -14928, 52080, -97968, -84000, 98112, -524400, -84048, 637488, 231288, -1558440, -343200, 844152, -2799840, 1152360, 1469160, -783240, 4153800, -4254000, -11947320, -498768, -264360, -559248, 32952432, -2061360, -37128408, -10466400, 18355512
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OFFSET
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1,1
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COMMENT
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Quadratic analogue of A117301 Determinants of 2 X 2 matrices of continuous blocks of 4 consecutive primes. See also: A001248 Squares of primes. The terminology "continuous" is used to distinguish from "discrete" which would be block 1: 4, 9, 25, 49; block 2: 121, 169, 289, 361; and so forth. Through n = 10^6, the number of negative values a(n) in this sequence appears to be consistently larger than the number of positive values.
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FORMULA
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a(n) = prime(n)^2*prime(n+3)^2 - prime(n+1)^2*prime(n+2)^2.
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EXAMPLE
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a(1) = -29
| 4, 9|
|25, 49|.
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CROSSREFS
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Cf. A000040, A001248, A117301.
Adjacent sequences: A118870 A118871 A118872 this_sequence A118874 A118875 A118876
Sequence in context: A044742 A142494 A067985 this_sequence A142622 A124957 A126416
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KEYWORD
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easy,sign
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AUTHOR
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Jonathan Vos Post (jvospost2(AT)yahoo.com), May 24 2006
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