A374908 Each term is the sum of the preceding term and its seven-segment total A006942.

0, 6, 12, 19, 27, 35, 45, 54, 63, 74, 81, 90, 102, 115, 124, 135, 147, 156, 169, 183, 197, 208, 226, 242, 256, 272, 285, 302, 318, 332, 347, 359, 375, 388, 407, 420, 435, 449, 463, 478, 492, 507, 521, 533, 548, 564, 579, 593, 609, 627, 641, 653, 669, 687, 703

Offset

0,2

Comments

The number of segments in each digit 0 to 9 is [6,2,5,5,4,5,6,3,7,6].

Conjecture: Taking the least significant digit of each term is not an eventually periodic sequence.

Links

Dominic McCarty, Table of n, a(n) for n = 0..10000

Formula

a(n) = a(n-1) + A006942(a(n-1)).

Example

For n=1, the preceding a(0) = 0 is 6 segments so that a(1) = 0 + 6 = 6.

Mathematica

s={0}; Do[AppendTo[s, Last[s]+ Plus @@ (IntegerDigits@ Last[s] /. {0 -> 6, 1 -> 2, 2 -> 5, 3 -> 5, 7 -> 3, 8 -> 7, 9 -> 6})], {n, 54}]; s (* James C. McMahon, Aug 19 2024 *)

Prog

(Python)
from itertools import islice
def b(n): return sum([6, 2, 5, 5, 4, 5, 6, 3, 7, 6][int(d)] for d in str(n))
def agen(): # generator of terms
    yield (an:=0)
    while True: yield (an:=an+b(an))
print(list(islice(agen(), 55))) # Michael S. Branicky, Jul 28 2024

Crossrefs

Cf. A006942, A219675.

Sequence in context: A187391 A081846 A078816 * A051936 A365702 A215342

Adjacent sequences: A374905 A374906 A374907 * A374909 A374910 A374911

Keyword

nonn,base,easy

Author

David J. Ellis, Jul 23 2024

Status

approved