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Search: id:A068623
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| A068623 |
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a(1) = 8; a(n+1) = smallest triangular number > a(n) formed by adding at least one digit to a(n). |
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4
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| 8, 28, 528, 18528, 184528, 18045028, 1800450028, 180004500028, 18000045000028, 1800000450000028, 180000004500000028, 18000000045000000028, 1800000000450000000028, 180000000004500000000028
(list; graph; listen)
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OFFSET
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1,1
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FORMULA
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For n>=5, a(n) = 18*10^(2*n-6) + 45*10^(n-3) + 28 [From Max Alekseyev (maxale(AT)gmail.com), Apr 25 2009]
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CROSSREFS
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Cf. A068618, A068619, A068621, A068622, A068624.
Sequence in context: A058289 A152014 A146977 this_sequence A155578 A115107 A035339
Adjacent sequences: A068620 A068621 A068622 this_sequence A068624 A068625 A068626
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KEYWORD
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base,nonn
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Feb 25 2002
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EXTENSIONS
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3 more terms from Ray G. Opao (1260(AT)email.com), Dec 14 2004
Extended by Max Alekseyev (maxale(AT)gmail.com), Apr 25 2009
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