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A225863 Primes for which both sum and product of digits are nonprimes. 1
19, 37, 53, 59, 73, 79, 97, 103, 107, 109, 127, 149, 163, 167, 181, 233, 239, 251, 257, 271, 277, 293, 307, 347, 349, 367, 383, 389, 419, 431, 433, 439, 457, 479, 491, 499, 503, 509, 521, 523, 541, 547, 563, 569, 587, 613, 617, 619, 631, 653, 659, 673 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

79 is a member since neither 7 + 9 = 16 nor 7 * 9 = 63 is prime.

MATHEMATICA

d[n_]:=IntegerDigits[n]; Select[Prime[Range[122]], !PrimeQ[Plus@@(x=d[#])] && !PrimeQ[Times@@x] &]

CROSSREFS

Cf. A046713.

Sequence in context: A272205 A245363 A109639 * A161705 A131600 A175546

Adjacent sequences:  A225860 A225861 A225862 * A225864 A225865 A225866

KEYWORD

nonn,base

AUTHOR

Jayanta Basu, May 18 2013

STATUS

approved

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Last modified March 25 02:32 EDT 2019. Contains 321450 sequences. (Running on oeis4.)