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Search: id:A118477
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| A118477 |
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Number of nonassociative rings with <= n elements. |
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+0
1
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| 1, 3, 5, 60, 62, 66, 68, 801356, 801521, 801525, 801527, 801637, 801639, 801643, 801647, 801648, 801650, 801652, 801707, 801709, 801713, 801715, 1603003, 1603168, 1603172, 1603174, 1603284, 1603286, 1603290, 1603294
(list; graph; listen)
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OFFSET
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1,2
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COMMENT
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Partial sums of A037292 Number of nonassociative rings with n elements. I do not know a(31), but if known, a(32) through a(39) are immediately derived. a(2), a(3), a(19) = 801707, and a(20) = 801709 are primes.
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REFERENCES
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"Reviews in Ring Theory, 1980-1984", American Mathematical Society, 1986; ISBN 0-8218-0097-3.
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FORMULA
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a(n) = SUM[i=1..n] A037292(i).
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EXAMPLE
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a(15) = 1 + 2 + 2 + 55 + 2 + 4 + 2 + 801288 + 165 + 4 + 2 + 110 + 2 + 4 + 4 = 801647.
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CROSSREFS
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Cf. A027623, A037292.
Sequence in context: A086340 A106914 A049190 this_sequence A076513 A145616 A122912
Adjacent sequences: A118474 A118475 A118476 this_sequence A118478 A118479 A118480
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KEYWORD
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nonn
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AUTHOR
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Jonathan Vos Post (jvospost3(AT)gmail.com), May 05 2006
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