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A155547 a(n) = prime(n) without prime digits in n. 1

%I #11 Jan 28 2024 16:44:29

%S 2,7,13,19,23,29,31,43,53,61,67,173,179,193,199,223,227,281,283,311,

%T 317,337,347,409,419,433,443,457,461,463,467,491,503,521,523,541,547,

%U 569,577,593,599,601,607,619,641,647,653,809,811,827,839,857,859,941,947

%N a(n) = prime(n) without prime digits in n.

%C Prime digit = 2, 3, 5 or 7.

%H Harvey P. Dale, <a href="/A155547/b155547.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = A000040(A084984(n)). - _R. J. Mathar_, Jan 25 2009

%p isA084984 := proc(n) local dgs ; dgs := convert(convert(n,base,10),set) ; if dgs intersect {2,3,5,7} <> {} then false; else true; fi; end: A084984 := proc(n) option remember ; local a ; if n = 1 then 1; else for a from procname(n-1)+1 do if isA084984(a) then RETURN(a) ; fi; od; fi; end: A155547 := proc(n) ithprime(A084984(n)) ; end: for n from 1 to 80 do printf("%d,",A155547(n)) ; od: # _R. J. Mathar_, Jan 25 2009

%t Prime[#]&/@Select[Range[200],NoneTrue[IntegerDigits[#],PrimeQ]&] (* _Harvey P. Dale_, Jan 28 2024 *)

%Y Cf. A000027, A000040.

%K nonn,base

%O 1,1

%A _Juri-Stepan Gerasimov_, Jan 24 2009

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Last modified March 28 11:59 EDT 2024. Contains 371254 sequences. (Running on oeis4.)