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A320870
Irregular table: row n >= 0 lists numbers m >= 0 such that n = A062028(m) := m + sum of digits of m.
0
0, 1, 2, 3, 4, 5, 10, 6, 11, 7, 12, 8, 13, 9, 14, 15, 20, 16, 21, 17, 22, 18, 23, 19, 24, 25, 30, 26, 31, 27, 32, 28, 33, 29, 34, 35, 40, 36, 41, 37, 42, 38, 43, 39, 44, 45, 50, 46, 51, 47, 52, 48, 53, 49, 54, 55, 60, 56, 61, 57, 62, 58, 63, 59, 64, 65, 70, 66, 71, 67, 72, 68, 73, 69, 74, 75, 80, 76, 81, 77, 82, 78, 83, 79, 84, 85, 90
OFFSET
0,3
COMMENTS
Row lengths are given by A230093.
EXAMPLE
The first nonempty rows are:
n | list of m
0 | 0 // since 0 = 0 + 0
2 | 1 // since 2 = 1 + 1
4 | 2 // etc.
6 | 3 // Below 10 every odd row is empty, but thereafter,
8 | 4 // only rows 20, 31, 42, ..., 108 (steps of 11),
10 | 5 // 110, 121, 132, ..., 198, etc. are empty.
11 | 10 // Since 11 = 10 + (1 + 0)
12 | 6
13 | 11 // The first prime that yields a prime: 11 + (1 + 1) = 13.
(...)
100 | 86 // The first row of length 2 is 101:
101 | 91, 100 // 101 = 91 + (9 + 1) = 100 + (1 + 0 + 0)
102 | 87
(...)
PROG
(PARI) A320870_row(n)=if(n, select(m->m+sumdigits(m)==n, [max(n-9*logint(n, 10)+8, n\/2)..n-1]), [0])
CROSSREFS
Cf. A007953 (sum of digits of n), A062028 (n + digit sum of n).
Cf. A230093 (number of m such that m + (sum of digits of m) is n).
Cf. A006064 (least m with row length n),
Cf. A003052 (Self or Colombian numbers: rows of length 0), A006378 (Colombian primes).
Cf. A320881 (indices of rows containing a prime), A048520 (primes among these).
Sequence in context: A302840 A357082 A360521 * A252022 A039697 A319131
KEYWORD
nonn,tabf,base
AUTHOR
M. F. Hasler, Nov 09 2018
STATUS
approved