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A062384 Numbers whose product of digits is 7 times the sum of the digits. 1
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; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..500

EXAMPLE

1447 belong to the sequence as (1*4*4*7)/(1 + 4 + 4 + 7) = 112/16 = 7.

PROG

(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)) ) } \\ Harry J. Smith, Aug 06 2009

CROSSREFS

Sequence in context: A228135 A188446 A251624 * A053345 A032505 A252855

Adjacent sequences:  A062381 A062382 A062383 * A062385 A062386 A062387

KEYWORD

nonn,base,easy

AUTHOR

Amarnath Murthy, Jun 27 2001

EXTENSIONS

Corrected and extended by Larry Reeves (larryr(AT)acm.org), Jul 06 2001

STATUS

approved

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Last modified March 31 03:48 EDT 2020. Contains 333136 sequences. (Running on oeis4.)