|
%I #37 Jan 06 2024 22:00:58
%S 32,56,88,175,176,182,212,218,227,248,293,295,323,331,338,362,377,386,
%T 394,397,398,409,439,446,457,481,499,508,563,571,595,599,635,637,655,
%U 671,728,751,752,755,761,767,779,820,821,826,827,847,848,857,869,878
%N Numbers k such that sum of digits of k-th prime equals sum of digits of k.
%C A090431(a(n)) = 0, A007953(a(n)) = A007605(a(n)).
%D Proposed by _G. L. Honaker, Jr._
%H T. D. Noe, <a href="/A033549/b033549.txt">Table of n, a(n) for n = 1..1000</a>
%e 131 is the 32nd prime and sum of digits of both is 5.
%t Select[Range[1000],Total[IntegerDigits[#]]==Total[IntegerDigits[ Prime[#]]]&] (* _Harvey P. Dale_, May 05 2011 *)
%o (Haskell)
%o a033549 n = a033549_list !! (n-1)
%o a033549_list = filter ((== 0) . a090431) [1..]
%o -- _Reinhard Zumkeller_, Mar 16 2014
%o (PARI) is(n,p=prime(n))=sumdigits(n)==sumdigits(p) \\ _Charles R Greathouse IV_, Feb 07 2017
%o (Python)
%o from sympy.ntheory.factor_ import digits
%o from sympy import prime
%o print([n for n in range(1, 1001) if sum(digits(n)[1:])==sum(digits(prime(n))[1:])]) # _Indranil Ghosh_, Jun 27 2017
%Y Cf. A033548, A071600.
%K nonn,base,nice
%O 1,1
%A Calculated by _Jud McCranie_
|
