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A062034
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Positive numbers whose product of digits is twice the sum of the digits.
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10
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36, 44, 63, 138, 145, 154, 183, 224, 242, 318, 381, 415, 422, 451, 514, 541, 813, 831, 1146, 1164, 1225, 1233, 1252, 1323, 1332, 1416, 1461, 1522, 1614, 1641, 2125, 2133, 2152, 2215, 2222, 2251, 2313, 2331, 2512, 2521, 3123, 3132, 3213, 3231, 3312, 3321
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OFFSET
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1,1
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LINKS
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EXAMPLE
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1225 belongs to the sequence as (1*2*2*5)/(1+2+2+5) =20/10 = 2.
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MATHEMATICA
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Select[Range[4000], Times@@IntegerDigits[#]==2Total[IntegerDigits[#]]&] (* Harvey P. Dale, Dec 11 2016 *)
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PROG
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(PARI) SumD(x)= { s=0; while (x>9, s=s+x-10*(x\10); x=x\10); return(s + x) }
ProdD(x)= { p=1; while (x>9, p=p*(x-10*(x\10)); x=x\10); return(p*x) }
{ n=-1; for (m=1, 2111281, if (ProdD(m)==2*SumD(m), write("b062034.txt", n++, " ", m)) ) } \\ Harry J. Smith, Jul 30 2009
(PARI) isok(n) = my(d=digits(n)); vecprod(d)==2*vecsum(d) \\ Mohammed Yaseen, Jul 28 2022
(Python)
from math import prod
def ok(n): d = list(map(int, str(n))); return prod(d) == 2*sum(d)
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CROSSREFS
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Cf. A011540, A034710, A062035, A062036, A062382, A062037, A062384, A062040, A062041, A062043, A062045.
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KEYWORD
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nonn,base,easy
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AUTHOR
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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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STATUS
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approved
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