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 A178837 Indices k such that the sums of the digits of Fibonacci(k) are prime numbers. 2
 3, 4, 5, 8, 9, 11, 14, 15, 18, 22, 25, 26, 27, 29, 30, 31, 34, 39, 41, 43, 45, 47, 51, 53, 54, 58, 61, 63, 65, 66, 67, 81, 85, 87, 90, 94, 99, 105, 107, 111, 113, 118, 122, 133, 135, 139, 147, 149, 151, 161, 167, 169, 173, 187, 191, 193, 194, 195, 198, 202, 213, 223 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE 3 is in the sequence because Fibonacci(3)= 2,and 2 is prime ; 113 is in the sequence because Fibonacci(113)= 184551825793033096366333 and sum of digits = 103 is prime. MAPLE with(combinat, fibonacci):nn:= 120: for n from 1 to 700 do:p:=fibonacci(n):l:=length(p):n0:=p:s:=0:for m from 1 to l do:q:=n0:u:=irem(q, 10):v:=iquo(q, 10):n0:=v :s:=s+u:od:if type(s, prime)=true then printf(`%d, `, n): else fi:od: MATHEMATICA Select[Range[300], PrimeQ[Total[IntegerDigits[Fibonacci[#]]]]&] (* Harvey P. Dale, Oct 22 2017 *) CROSSREFS Cf. A000045, A065398. Sequence in context: A047601 A029675 A030310 * A212011 A207005 A316976 Adjacent sequences:  A178834 A178835 A178836 * A178838 A178839 A178840 KEYWORD nonn,base AUTHOR Michel Lagneau, Jun 17 2010 STATUS approved

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Last modified April 6 02:20 EDT 2020. Contains 333267 sequences. (Running on oeis4.)