A119461 Zero-free numbers with digit sum equal to 7.

7, 16, 25, 34, 43, 52, 61, 115, 124, 133, 142, 151, 214, 223, 232, 241, 313, 322, 331, 412, 421, 511, 1114, 1123, 1132, 1141, 1213, 1222, 1231, 1312, 1321, 1411, 2113, 2122, 2131, 2212, 2221, 2311, 3112, 3121, 3211, 4111, 11113, 11122, 11131, 11212, 11221, 11311, 12112, 12121, 12211, 13111, 21112, 21121, 21211, 22111, 31111, 111112, 111121, 111211, 112111, 121111, 211111, 1111111

Offset

1,1

Comments

There are exactly 64 such numbers while numbers with digit sum equal to 7 (A052221) are infinite.

Links

Table of n, a(n) for n=1..64.

Mathematica

Union[Flatten[Table[FromDigits/@Select[Tuples[Range[7], n], Total[#]==7&], {n, 7}]]] (* Harvey P. Dale, Aug 29 2015 *)

Prog

(Python)
def ok(n): s = str(n); return '0' not in s and sum(map(int, s)) == 7
print(list(filter(ok, range(1111112)))) # Michael S. Branicky, Jul 16 2021

Crossrefs

Subsequence of A052221.

Sequence in context: A217009 A017245 A052221 * A326664 A028560 A190530

Adjacent sequences: A119458 A119459 A119460 * A119462 A119463 A119464

Keyword

base,fini,full,nonn

Author

Zak Seidov, May 20 2006

Status

approved