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A097640 Numbers n such that n=(d_1+d_2+...+d_k)*prime(d_1+d_2+...+d_k) where d_1 d_2 ... d_k is the decimal expansion of n. 2
152, 207, 444, 1098 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..4.

EXAMPLE

444 is in the sequence because 444=(4+4+4)*prime(4+4+4).

MATHEMATICA

denQ[n_]:=Module[{tidn=Total[IntegerDigits[n]]}, n==tidn Prime[tidn]]; Select[Range[1100], denQ] (* Harvey P. Dale, May 08 2012 *)

CROSSREFS

Cf. A097641.

Sequence in context: A289821 A234348 A185394 * A253367 A253360 A252363

Adjacent sequences:  A097637 A097638 A097639 * A097641 A097642 A097643

KEYWORD

base,fini,full,nonn

AUTHOR

Farideh Firoozbakht, Aug 21 2004

STATUS

approved

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Last modified October 16 20:09 EDT 2021. Contains 348044 sequences. (Running on oeis4.)