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Search: id:A062384
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| A062384 |
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Numbers whose product of digits is 7 times the sum of the digits. |
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+0
1
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| 279, 297, 357, 375, 537, 573, 729, 735, 753, 792, 927, 972, 1447, 1474, 1744, 4147, 4174, 4417, 4471, 4714, 4741, 7144, 7414, 7441, 11367, 11376, 11637, 11673, 11736, 11763, 12247, 12274, 12427, 12472, 12724, 12742, 13167, 13176, 13617, 13671
(list; graph; listen)
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OFFSET
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1,1
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LINKS
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Harry J. Smith, Table of n, a(n) for n=1,...,500
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EXAMPLE
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1447 belong to the sequence as (1*4*4*7)/(1+4+4+7) =112/16 = 7.
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PROGRAM
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(PARI) SumD(x)= { s=0; while (x>9, s+=x-10*(x\10); x\=10); return(s + x) } ProdD(x)= { p=1; while (x>9, p*=(x-10*(x\10)); x\=10); return(p*x) } { n=0; for (m=1, 10^9, if (ProdD(m)==7*SumD(m), write("b062384.txt", n++, " ", m); if (n==500, break)) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Aug 06 2009]
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CROSSREFS
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Sequence in context: A048525 A154231 A056995 this_sequence A053345 A032505 A038656
Adjacent sequences: A062381 A062382 A062383 this_sequence A062385 A062386 A062387
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KEYWORD
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nonn,base,easy
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Jun 27 2001
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EXTENSIONS
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Corrected and extended by Larry Reeves (larryr(AT)acm.org), Jul 06 2001
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