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Search: id:A163744
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| 1, 1, 3, 4, 23, 23, 608, 3703, 59063, 65975, 65975, 65975, 3227648, 83180983
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OFFSET
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1,3
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COMMENT
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Smallest positive m such that m-th truncated square pyramid number tsp(m)=m*(7*m-1)*(2*m-1)/6 is divisible by n!, n=0,1,.. .
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EXAMPLE
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a(3)=3 because tsp(3)=126 is divisible by 3!: 126/3!=21
a(5)=23 because tsp(23)=27600 is divisible by 5!: 27600/5!=230
a(6)=608 because tsp(608)=523875600 is divisible by 6!: 523875600/6!=727605.
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CROSSREFS
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Cf. A050410 Truncated square pyramid numbers:a(n)=sum(k^2, k=n..2*n-1)=(1/6)n(7n-1)(2n-1).
Sequence in context: A012247 A057791 A122660 this_sequence A042595 A002351 A042035
Adjacent sequences: A163741 A163742 A163743 this_sequence A163745 A163746 A163747
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KEYWORD
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nonn
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AUTHOR
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Zak Seidov (zakseidov(AT)gmail.com), Aug 03 2009
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