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 A033548 Honaker primes: primes P(k) such that sum of digits of P(k) equals sum of digits of k. 28
 131, 263, 457, 1039, 1049, 1091, 1301, 1361, 1433, 1571, 1913, 1933, 2141, 2221, 2273, 2441, 2591, 2663, 2707, 2719, 2729, 2803, 3067, 3137, 3229, 3433, 3559, 3631, 4091, 4153, 4357, 4397, 4703, 4723, 4903, 5009, 5507, 5701, 5711, 5741, 5801, 5843 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A090431(A049084(a(n))) = 0. REFERENCES Proposed by G. L. Honaker, Jr. LINKS T. D. Noe and Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 (first 1000 terms from Noe) EXAMPLE 131 is the 32nd prime and sum of digits of both is 5. MAPLE P:=proc(n) local a; a:=ithprime(n); if convert(convert(n, base, 10), `+`)=convert(convert(a, base, 10), `+`) then a; fi; end: seq(P(i), i=1..10^3); # Paolo P. Lava, Jun 29 2017 MATHEMATICA Prime[ Select[ Range[ 2000 ], Apply[ Plus, IntegerDigits[ # ] ] == Apply[ Plus, IntegerDigits[ Prime[ # ] ] ] & ] ] (* Santi Spadaro, Oct 14 2001 *) Select[ Prime@ Range@ 5927, Plus @@ IntegerDigits@ # == Plus @@ IntegerDigits@ PrimePi@ # &]  (* Robert G. Wilson v, Jun 07 2009 *) nn=800; Transpose[Select[Thread[{Prime[Range[nn]], Range[nn]}], Total[IntegerDigits[First[#]]]== Total[ IntegerDigits[ Last[#]]]&]][[1]] (* Harvey P. Dale, Jun 13 2011 *) PROG (Haskell) a033548 n = a033548_list !! (n-1) a033548_list = filter ((== 0) . a090431 . a049084) a000040_list -- Reinhard Zumkeller, Mar 16 2014 (PARI) is(n)=isprime(n) && sumdigits(n)==sumdigits(primepi(n)) \\ Charles R Greathouse IV, Jun 18 2015 (Python) from sympy.ntheory.factor_ import digits from sympy import primepi, primerange print [n for n in primerange(1, 5901) if (sum(digits(n)[1:])==sum(digits(primepi(n))[1:]))] # Indranil Ghosh, Jun 27 2017, after Charles R Greathouse IV CROSSREFS Cf. A033549, A049084, A072439, A090431. Sequence in context: A142616 A207527 A132249 * A117477 A089316 A242846 Adjacent sequences:  A033545 A033546 A033547 * A033549 A033550 A033551 KEYWORD nonn,base,nice AUTHOR Calculated by Jud McCranie EXTENSIONS More terms from Robert G. Wilson v, Jun 07 2009 STATUS approved

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Last modified October 23 10:14 EDT 2019. Contains 328345 sequences. (Running on oeis4.)