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A280993 Primes such that the absolute value of the difference between the largest digit and the sum of all the other digits is a cube. 2

%I #64 Dec 31 2021 19:31:33

%S 11,19,23,43,67,89,101,109,113,131,157,167,179,197,199,211,223,241,

%T 257,263,269,311,313,331,337,347,353,359,373,379,397,421,431,449,461,

%U 463,523,541,571,593,607,617,641,643,661,683,719,733,739,743

%N Primes such that the absolute value of the difference between the largest digit and the sum of all the other digits is a cube.

%C If the largest digit L (say) is repeated, the criterion is that |L - (sum of all digits except for one copy of L)| is a cube.

%H David A. Corneth, <a href="/A280993/b280993.txt">Table of n, a(n) for n = 1..10000</a>

%e The prime 2731 is a term, because 7-2-3-1 = 1 is a cube.

%e The prime 13 is not in the sequence, as 3-1 = 2, and 2 is not a cube.

%e The prime 313 is a term because |3 - (1+3)| = 1 is a cube.

%t Select[Prime[Range[150]],IntegerQ[Surd[Abs[Max[IntegerDigits[#]]-Total[ Most[ Sort[IntegerDigits[#]]]]],3]]&] (* _Harvey P. Dale_, Dec 31 2021 *)

%o (PARI) listA280993(k, {k0=5})={my(H=List(), y); forprime(z=prime(k0), prime(k), y=digits(z); if(ispower(abs(vecsum(y)-2*vecmax(y)),3), listput(H, z))); return(vector(#H, i, H[i]))} \\ Looks for those belonging terms between prime(k0) and prime(k). - _R. J. Cano_, Feb 06 2017

%Y A156753 and A156979 are subsequences.

%K nonn,easy,base

%O 1,1

%A _Osama Abuajamieh_, Jan 14 2017

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