A368194 - OEIS

A368194

Irregular table T(n, k), n > 0, k = 1..A368195(n), read by rows: the n-th row lists the numbers that can be obtained by replacing any positive number without leading zeros, say m, appearing in the decimal expansion of n by one of the divisors of m.

1, 1, 2, 1, 3, 1, 2, 4, 1, 5, 1, 2, 3, 6, 1, 7, 1, 2, 4, 8, 1, 3, 9, 1, 2, 5, 10, 1, 11, 1, 2, 3, 4, 6, 11, 12, 1, 11, 13, 1, 2, 7, 11, 12, 14, 1, 3, 5, 11, 15, 1, 2, 4, 8, 11, 12, 13, 16, 1, 11, 17, 1, 2, 3, 6, 9, 11, 12, 14, 18, 1, 11, 13, 19, 1, 2, 4, 5, 10, 20

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

COMMENTS

The n-th row starts with 1, ends with n, and contains the divisors of n (A027750).

LINKS

Rémy Sigrist, Table of n, a(n) for n = 1..16938 (rows for n = 1..1000 flattened)

Rémy Sigrist, PARI program

Index entries for sequences related to decimal expansion of n

FORMULA

T(n, 1) = 1.

T(n, A368195(n)) = n.

EXAMPLE

Table T(n, k) begins:

1, 2;

1, 3;

1, 2, 4;

1, 5;

1, 2, 3, 6;

1, 7;

1, 2, 4, 8;

1, 3, 9;

1, 2, 5, 10;

1, 11;

1, 2, 3, 4, 6, 11, 12;

1, 11, 13;

1, 2, 7, 11, 12, 14;

1, 3, 5, 11, 15;

1, 2, 4, 8, 11, 12, 13, 16;

1, 11, 17;

1, 2, 3, 6, 9, 11, 12, 14, 18;

...

PROG

(PARI) See Links section.

CROSSREFS

Cf. A027750, A323286, A342072, A368195, A368313 (binary variant).

Sequence in context: A162306 A376248 A348135 * A233773 A027750 A275055

Adjacent sequences: A368191 A368192 A368193 * A368195 A368196 A368197

KEYWORD

nonn,base,tabf

AUTHOR

Rémy Sigrist, Dec 16 2023

STATUS

approved