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A053779 Numbers k such that the sum of the first k composite numbers is palindromic. 2

%I

%S 1,22,24,167,202,226,1443,2380,3190,3952,4220,16827,26304,37612,40813,

%T 213501,376524,1920079,2061085,2635057,3463613,4268588,16513206,

%U 68101132,166428703,207224360,403784450,421279478,1384813481

%N Numbers k such that the sum of the first k composite numbers is palindromic.

%C Sequence lists numbers k such that 4 + 6 + 8 + 9 + 10 + 12 + ... + composite(k) is palindromic. For the corresponding values of composite(k) see A057959.

%H P. De Geest, <a href="http://www.worldofnumbers.com/firstpal.htm#sfn3">Palindromic Sums</a>

%H C. Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_089.htm">PrimePuzzle 89</a>

%t Position[Accumulate[Select[Range[146*10^7],CompositeQ]],_?(PalindromeQ[ #] &)] // Flatten (* _Harvey P. Dale_, Sep 29 2018 *)

%Y Cf. A002808, A002113, A053780.

%K base,nonn

%O 1,2

%A _G. L. Honaker, Jr._, Mar 29 2000

%E More terms from _G. L. Honaker, Jr._, Mar 29 2000

%E Further terms added by _Patrick De Geest_, Nov 15 2000

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Last modified November 23 16:18 EST 2020. Contains 338590 sequences. (Running on oeis4.)