A062034 Positive numbers whose product of digits is twice the sum of the digits.

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

Offset: 1

Author

Amarnath Murthy, Jun 27 2001

Keywords

• nonn
• base
• easy

Examples

			1225 belongs to the sequence as (1*2*2*5)/(1+2+2+5) =20/10 = 2.
		

Links

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

Crossrefs

Cf. A011540, A034710, A062035, A062036, A062382, A062037, A062384, A062040, A062041, A062043, A062045.

Programs

Mathematica

Select[Range[4000],Times@@IntegerDigits[#]==2Total[IntegerDigits[#]]&] (* Harvey P. Dale, Dec 11 2016 *)

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)
print([k for k in range(1, 4000) if ok(k)]) # Michael S. Branicky, Jul 28 2022

Extensions

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

Offset corrected by Mohammed Yaseen, Jul 28 2022