A138566 Numbers n whose digits satisfy the following Diophantine equation: P = (X1* ... *Xr)/(X1+ ... +Xr), where P = prime number, Xi = digits of n.

36, 44, 63, 66, 138, 145, 154, 159, 167, 176, 183, 195, 224, 235, 242, 253, 257, 275, 279, 297, 318, 325, 333, 345, 352, 354, 357, 375, 381, 415, 422, 435, 451, 453, 514, 519, 523, 527, 532, 534, 537, 541, 543, 572, 573, 591, 617, 671, 716, 725, 729, 735

Offset

1,1

Links

Table of n, a(n) for n=1..52.

Example

n = 761, we have (7*6*1)/(7+6+1) = 3; a(56)= 761.
n = 792, we have (7*9*2)/(7+9+2) = 7; a(57)= 792.
n = 813, we have (8*1*3)/(8+1+3) = 2; a(58)= 813.

Mathematica

Block[{i = k, r = {}}, r = Table[p = IntegerDigits@i; If[PrimeQ[Times @@ p/Total@p], k, Nothing], {k, 735}]; r] (* Mikk Heidemaa, May 26 2024 *)

Crossrefs

Subsequence of A038367.

Cf. A137923.

Sequence in context: A266242 A274241 A062519 * A062034 A250641 A168107

Adjacent sequences: A138563 A138564 A138565 * A138567 A138568 A138569

Keyword

base,easy,nonn

Author

Ctibor O. Zizka, May 12 2008

Status

approved