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A077526 Triangle in which the n-th row contains n palindromes beginning with n. 2

%I #12 Dec 05 2013 19:55:53

%S 1,2,22,3,33,303,4,44,404,414,5,55,505,515,525,6,66,606,616,626,636,7,

%T 77,707,717,727,737,747,8,88,808,818,828,838,848,858,9,99,909,919,929,

%U 939,949,959,969,101,1001,10001,10101,10201,10301,10401,10501,10601,10701

%N Triangle in which the n-th row contains n palindromes beginning with n.

%e Triangle begins:

%e 1

%e 2 22

%e 3 33 303

%e 4 44 404 414

%e 5 55 505 515 525

%e 6 66 606 616 626 636

%o (PARI) ispal(v) = {for(i = 1, #v\2, if (v[i] != v[#v-i+1], return(0));); return(1);};

%o startwith(d, j) = {dj = digits(j); for (k = 1, #dj, if (d[k] != dj[k], return (0));); return (1);}

%o tabl(nn) = {for (i = 1, nn, j = i; nb = 0; while (nb < i, d = digits(j); if (startwith(d, i) && ispal(d), print1(j, ", "); nb++); j++;); print(););} \\ _Michel Marcus_, Sep 13 2013

%Y Cf. A077525, A077527.

%K base,nonn,tabl

%O 1,2

%A _Amarnath Murthy_, Nov 08 2002

%E Term 10001 included by _Michel Marcus_, Sep 13 2013

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)