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 A046431 Sum of digits of a(n) raised to its digits powers is prime. 11
 10, 11, 12, 14, 20, 21, 23, 27, 32, 34, 40, 41, 43, 47, 72, 74, 100, 101, 103, 110, 111, 113, 130, 131, 157, 175, 236, 263, 289, 298, 300, 301, 310, 311, 326, 348, 355, 362, 384, 438, 445, 454, 458, 483, 485, 507, 517, 535, 544, 548, 553, 570, 571, 584, 623 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS If p is prime, then R_p (see A002275) is a term, so the sequence is infinite. - Marius A. Burtea, Sep 18 2019 LINKS Marius A. Burtea, Table of n, a(n) for n = 0..5000 EXAMPLE 10 is a term:  10 -> 1^1 + 0^0 = 2 (prime). 289 is a term:  289 -> 2^2 + 8^8 + 9^9 = 404197709 (prime). MAPLE q:= n-> (l-> isprime(add(i^i, i=l)))(convert(n, base, 10)): select(q, [\$0..1000])[];  # Alois P. Heinz, Sep 18 2019 MATHEMATICA sopQ[n_] := PrimeQ[Total[#^# & /@ (IntegerDigits[n] /. {0 -> 1})]]; Select[Range[625], sopQ[#] &] (* Jayanta Basu, Jun 25 2013 *) PROG (MAGMA) [k:k in [1..650]| IsPrime( &+[a[s]^(a[s]): s in [1..# a]]) where a is Intseq(k) ]; // Marius A. Burtea, Sep 18 2019 CROSSREFS Cf. A046432-A046441. Sequence in context: A110186 A098945 A323190 * A108697 A109279 A258744 Adjacent sequences:  A046428 A046429 A046430 * A046432 A046433 A046434 KEYWORD nonn,base,changed AUTHOR Patrick De Geest, Jul 15 1998 STATUS approved

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Last modified October 16 08:15 EDT 2019. Contains 328051 sequences. (Running on oeis4.)