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A230085 Smallest of four consecutive primes whose product of digits is equal and nonzero. 0
336737123, 812444239, 1731191219, 2187575239, 2549315123, 2672459219, 2721498343, 2778476123, 2781452239, 2924114819, 2925926819, 3232115219, 3441686219, 3579455219, 3617846123, 3755345219, 3943951637 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..17.

EXAMPLE

336737123 is in the sequence because 336737123, 336737161, 336737213 and 336737231 are consecutive primes and the product of the digits of each = 47628.

MATHEMATICA

a = {}; m = 1; s = 1; Do[If[(y = Apply[Times, IntegerDigits[x = Prime[n]]]) == s  && s != 0,  m = m + 1; If[m > 3, AppendTo[a, Prime[n - 3]]], m = 1]; s = y, {n, 1, 200000000}]; a

pdeQ[{a_, b_, c_, d_}]:=Module[{u=Union[Times@@@(IntegerDigits/@{a, b, c, d})]}, Length[ u] ==1&&u[[1]]>0]; Transpose[Select[Partition[Prime[Range[ 19*10^7]], 4, 1], pdeQ]][[1]] (* Harvey P. Dale, Jan 27 2015 *)

CROSSREFS

Cf. A230082, A230083, A230084, A007954, A053666.

Sequence in context: A222978 A271112 A233703 * A204337 A113739 A159448

Adjacent sequences:  A230082 A230083 A230084 * A230086 A230087 A230088

KEYWORD

nonn,base

AUTHOR

Shyam Sunder Gupta, Oct 08 2013

STATUS

approved

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Last modified October 21 08:47 EDT 2019. Contains 328292 sequences. (Running on oeis4.)