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A103920
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Central numbers in triangle A103728.
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0
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-1, 5, -17, -229, 853, 12113, -46061, -674761, 38733269, -150113729, 8829861373, 134484418361, -525740249453, -8058251350417, 486561579496253, -29557651813108141, 116325817932650581, -7111675770821993117, -110606189396709847609
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OFFSET
| 2,2
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COMMENTS
| a(n) given by the formula below is indeed an integer because A103728 is an integer triangle.
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FORMULA
| a(n)= A103728(n, b(n)), n>=2, with b(n):=(p(n)-1)/2=A005097(n-1) and p(n)= A000040(n) (n-th prime number).
a(n)=(1+((-1)^b(n))*2*b(n)*binomial(2*b(n), b(n)))/(2*b(n)+1), n>=2, with b(n) defined above.
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CROSSREFS
| Sequence in context: A206328 A096407 A062230 * A086362 A195570 A191500
Adjacent sequences: A103917 A103918 A103919 * A103921 A103922 A103923
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KEYWORD
| sign,easy
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AUTHOR
| Wolfdieter Lang (wolfdieter.lang_AT_physik_DOT_uni-karlsruhe_DOT_de), Mar 24 2005
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