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Primes expressible as the sum of 4 consecutive palindromes.
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%I #12 Nov 24 2022 12:45:26

%S 827,1231,1553,2039,3169,3251,159683,199687,319699,1999969987,

%T 2000030009,3200030021,80000299997,200000300009,20000003000009,

%U 1599999969999983,15999999996999999983,24000000003000000013

%N Primes expressible as the sum of 4 consecutive palindromes.

%H Patrick De Geest, <a href="http://www.worldofnumbers.com/index.html">World!Of Numbers</a>

%F Primes of either of two forms: 4*(a+1)*10^(2*k) + 3*10^k + 4*a - 7 or 4*(a+1)*10^(2*k) - 3*10^k + 4*a - 29, where 1 <= a <= 8 and k is positive integer. - _Max Alekseyev_, Apr 12 2009

%e 319699 = 79797 + 79897 + 79997 + 80008.

%t Select[Total/@Partition[Select[Range[10^6],PalindromeQ],4,1],PrimeQ] (* The program generates the first 9 terms of the sequence. *) (* _Harvey P. Dale_, Nov 24 2022 *)

%Y Cf. A000040, A002113.

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Sep 15 1998

%E Extended by _Max Alekseyev_, Apr 12 2009