262122

Appears in sequences

• Number of primitive (aperiodic) palindromes using a maximum of two different symbols.at n=34A056458
• Number of primitive (aperiodic) palindromes using exactly two different symbols.at n=34A056463
• Number of primitive (period n) periodic palindromes using a maximum of two different symbols.at n=34A056493
• Number of primitive (period n) periodic palindromes using exactly two different symbols.at n=34A056498
• Final term of commas sequence (cf. A121805) if start at 1 and do the calculations in base n; or -1 if the sequence is infinite.at n=6A367605