A138481 -id:A138481 - cp's OEIS frontend

A138480 Autobiographical numbers: the first digit specifies how many 0's in the number, the next digit specifies how many 1's, etc. This version is not limited to 10 digits.

1210, 2020, 21200, 3211000, 42101000, 521001000, 6210001000, 72100001000, 821000001000, 9210000001000

Offset: 1

Martin Fuller, Mar 20 2008

			72100001000 has 7 digits equal to "0", 2 digits equal to "1", 1 digit each "2" and "7" and no other digits.

E. Angelini, "Jeux de suites", in Dossier Pour La Science, pp. 32-35, Volume 59 (Jeux math'), April/June 2008, Paris.

Shyam Sunder Gupta, On Some Special Numbers, Exploring the Beauty of Fascinating Numbers, Springer (2025) Ch. 22, 527-565.
Tanya Khovanova, Can you solve the Leonardo da Vinci riddle?, TED-Ed YouTube channel.

Autobiographical numbers up to 10 digits: A046043. Mutually-praising pairs: A138481 and A138482.

A138482 Mutually-praising pairs excluding autobiographical numbers A138480. Version 2: numbers may have more than 10 digits.

Original entry on oeis.org

130, 230, 430, 530, 630, 730, 830, 930, 1101, 2210, 10110, 11200, 23100, 43100, 53100, 63100, 73100, 83100, 93100, 211100, 230100, 311100, 411100, 430100, 511100, 530100, 611100, 630100, 711100, 730100, 811100, 830100, 911100, 930100

Offset: 1

Martin Fuller, Mar 20 2008

			130 and 1101 are a mutually-praising pair: 130 specifies a number with 1 digit equal to "0", 3 digit "1" and nothing else. 1101 specifies 1 digit "0", 1 digit "1", no digits "2" and 1 digit "3". 73100 and 21010001000 is the first pair with a number of more than 10 digits.

Martin Fuller, Table of n, a(n) for n = 1..172
Tanya Khovanova, Autobiographical Numbers

Cf. A046043, A138480, A138481.

cp's OEIS Frontend

A138480 Autobiographical numbers: the first digit specifies how many 0's in the number, the next digit specifies how many 1's, etc. This version is not limited to 10 digits.

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