A353736 Number of n-digit terms in A353007.

5, 21, 122, 765, 5000, 34581, 249152, 1843485, 14184320, 111117141, 890892032, 7338139005, 60554071040, 518102719701, 4409318285312, 38356828343325, 341939662684160, 2933245707834261, 28085287524564992, 229163829314312445, 2425706018857287680, 18151248585662332821

Offset

1,1

Comments

From Bernard Schott, Jul 14 2022: (Start)

Conjecture 1: lim_{n->oo} a(2n+1)/a(2n-1) = 100.

Conjecture 2: lim_{n->oo} a(2n+2)/a(2n) = 81.

These conjectures are the same as for A353735. (End)

Links

Michael S. Branicky, Table of n, a(n) for n = 1..1002

Example

There are five 1-digit terms in A353007: 0, 2, 4, 6, 8. Thus, a(1) = 5.

Prog

(Python)
def isA353007(n):
    digits = list(map(int, str(n)))
    return all(digits.count(d)%2 != d%2 for d in set(digits))
def a(n):
    start = 0 if n == 1 else 10**(n-1)
    return sum(1 for i in range(start, 10**n) if isA353007(i))
print([a(n) for n in range(1, 7)]) # Michael S. Branicky, May 06 2022

Crossrefs

Cf. A333369, A353007, A353735.

Sequence in context: A002711 A218962 A124311 * A208593 A213009 A316102

Adjacent sequences: A353733 A353734 A353735 * A353737 A353738 A353739

Keyword

nonn,base

Author

Michael S. Branicky, May 06 2022

Status

approved