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A077526 Triangle in which the n-th row contains n palindromes beginning with n. 2
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 (list; table; graph; refs; listen; history; text; internal format)
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

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Last modified January 19 16:49 EST 2022. Contains 350466 sequences. (Running on oeis4.)