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A099069 Numbers n such that n=prime(d_1*d_2*...*d_k)-phi(d_1+d_2+...+d_k) where d_1 d_2 ... d_k is the decimal expansion of n. 2
1, 2, 3, 19, 35497 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

LINKS

C. Rivera, Puzzle 279The Prime Puzzles & Problems connection.

EXAMPLE

35497 is in the sequence because 35497=prime(3*5*4*9*7)-phi(3+5+4+9+7).

MATHEMATICA

Do[h=IntegerDigits[n]; l=Length[h]; If[ !MemberQ[h, 0]&&n==Prime[Product[h[[k]], {k, l}]]-EulerPhi[Sum[h[[k]], {k, l}]], Print[n]], {n, 6000000}]

CROSSREFS

Cf. A099067, A099068, A097223, A097227.

Sequence in context: A032077 A014547 A066735 * A038584 A108022 A108884

Adjacent sequences:  A099066 A099067 A099068 * A099070 A099071 A099072

KEYWORD

base,more,nonn

AUTHOR

Farideh Firoozbakht (baran4560(AT)yahoo.com), Oct 29 2004

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.