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A033549
Numbers k such that sum of digits of k-th prime equals sum of digits of k.
12
32, 56, 88, 175, 176, 182, 212, 218, 227, 248, 293, 295, 323, 331, 338, 362, 377, 386, 394, 397, 398, 409, 439, 446, 457, 481, 499, 508, 563, 571, 595, 599, 635, 637, 655, 671, 728, 751, 752, 755, 761, 767, 779, 820, 821, 826, 827, 847, 848, 857, 869, 878
OFFSET
1,1
COMMENTS
A090431(a(n)) = 0, A007953(a(n)) = A007605(a(n)).
REFERENCES
Proposed by G. L. Honaker, Jr.
EXAMPLE
131 is the 32nd prime and sum of digits of both is 5.
MATHEMATICA
Select[Range[1000], Total[IntegerDigits[#]]==Total[IntegerDigits[ Prime[#]]]&] (* Harvey P. Dale, May 05 2011 *)
PROG
(Haskell)
a033549 n = a033549_list !! (n-1)
a033549_list = filter ((== 0) . a090431) [1..]
-- Reinhard Zumkeller, Mar 16 2014
(PARI) is(n, p=prime(n))=sumdigits(n)==sumdigits(p) \\ Charles R Greathouse IV, Feb 07 2017
(Python)
from sympy.ntheory.factor_ import digits
from sympy import prime
print([n for n in range(1, 1001) if sum(digits(n)[1:])==sum(digits(prime(n))[1:])]) # Indranil Ghosh, Jun 27 2017
CROSSREFS
Sequence in context: A118617 A259716 A033907 * A117478 A008434 A130447
KEYWORD
nonn,base,nice
AUTHOR
Calculated by Jud McCranie
STATUS
approved