A334822 Palindromes k such that k*sod(k) and k/sod(k) are both palindromes, where sod(k) denotes the sum of digits of k (A007953).

1, 2, 3, 144689999986441, 154698898896451, 226589999985622, 234779999977432, 243788999887342, 244788898887442, 253698898896352, 254689878986452, 254788878887452, 254797797797452, 333878999878333, 334878898878433, 335598898895533, 336589878985633, 336688878886633

Offset

1,2

Comments

Intersection of A002113 and A229549 and A334416. Palindromes in A334533.

For the first 10000 terms, most of them have digit sum 91. The only terms a(n) for n <= 10000 for which the digit sum is not 91 are 1, 2, 3 and a(1076) = 426666666666666624. - Chai Wah Wu, May 15 2020

Links

Chai Wah Wu, Table of n, a(n) for n = 1..10000

Example

35479654545697453 is a palindrome whose sum of digits is 91. 35479654545697453/91 = 389886313688983 and 35479654545697453*91 = 3228648563658468223 which are both palindromes. So 35479654545697453 is a term.

Crossrefs

Cf. A002113, A007953, A229549, A334416, A334533.

Sequence in context: A307255 A176649 A216979 * A082871 A321406 A166926

Adjacent sequences: A334819 A334820 A334821 * A334823 A334824 A334825

Keyword

nonn,base

Author

Chai Wah Wu, May 12 2020

Status

approved