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A352463 Numbers k with the property that the product of the digits of k starts k. 1
1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 21, 31, 41, 51, 61, 71, 81, 91, 111, 126, 153, 211, 243, 311, 362, 411, 511, 611, 711, 811, 911, 1111, 1216, 1223, 1232, 1261, 1288, 1359, 1449, 1513, 1531, 1755, 2111, 2413, 2431, 3111, 3612, 3621, 3844, 4111, 5111, 6111, 6728, 7111, 7357, 8111, 9111, 11111, 11278, 11287 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..60.

EXAMPLE

a(10) = 11 starts with 1, which is the product 1*1;

a(20) = 126 starts with 12, which is the product 1*2*6;

a(42) = 1755 starts with 175, which is the product ; 1*7*5*5; etc.

MATHEMATICA

q[n_] := Module[{d = IntegerDigits[n], p, dp, ndp}, p = Times @@ d; dp = IntegerDigits[p]; ndp = Length[dp]; dp == d[[1 ;; ndp]]]; Select[Range[12000], q] (* Amiram Eldar, Mar 18 2022 *)

PROG

(Python)

from math import prod

def ok(n): s = str(n); return s.startswith(str(prod(map(int, s))))

print([k for k in range(1, 12000) if ok(k)]) # Michael S. Branicky, Mar 17 2022

CROSSREFS

Cf. A203565, A352461, A352464.

Sequence in context: A321990 A076641 A076643 * A326402 A127204 A331626

Adjacent sequences:  A352460 A352461 A352462 * A352464 A352465 A352466

KEYWORD

base,nonn

AUTHOR

Eric Angelini and Carole Dubois, Mar 17 2022

STATUS

approved

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Last modified June 26 12:56 EDT 2022. Contains 354883 sequences. (Running on oeis4.)