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

1, 2, 22, 3, 33, 303, 4, 44, 404, 414, 5, 55, 505, 515, 525, 6, 66, 606, 616, 626, 636, 7, 77, 707, 717, 727, 737, 747, 8, 88, 808, 818, 828, 838, 848, 858, 9, 99, 909, 919, 929, 939, 949, 959, 969, 101, 1001, 10001, 10101, 10201, 10301, 10401, 10501, 10601, 10701

Offset

1,2

Links

Table of n, a(n) for n=1..55.

Example

Triangle begins:
1
2 22
3 33 303
4 44 404 414
5 55 505 515 525
6 66 606 616 626 636

Prog

(PARI) ispal(v) = {for(i = 1, #v\2, if (v[i] != v[#v-i+1], return(0)); ); return(1); };
startwith(d, j) = {dj = digits(j); for (k = 1, #dj, if (d[k] != dj[k], return (0)); ); return (1); }
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

Crossrefs

Cf. A077525, A077527.

Sequence in context: A328993 A336768 A180700 * A083764 A336324 A335886

Adjacent sequences: A077523 A077524 A077525 * A077527 A077528 A077529

Keyword

base,nonn,tabl

Author

Amarnath Murthy, Nov 08 2002

Extensions

Term 10001 included by Michel Marcus, Sep 13 2013

Status

approved