cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A067284 a(n) = number of integers k such that k is not of the form m + reverse(m) for any m (cf. A067031) and A067030(n) occurs in the 'Reverse and Add' trajectory of k.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 5, 5, 8, 7, 12, 9, 1, 13, 21, 14, 1, 6, 11, 1, 4, 14, 1, 2, 9, 1, 2, 1, 2, 1, 22, 1, 2, 1, 2, 2, 3, 2, 3, 2, 3, 2, 16, 2, 3, 3, 5, 3, 4, 3, 5, 3, 4, 3, 30, 4, 6, 5, 5, 4, 6, 5, 5, 4, 6, 15, 8, 6, 6, 5, 8, 6, 6, 5, 8, 6, 9, 24, 7, 6, 9, 8, 7, 6, 9, 7, 12, 9, 8, 20
Offset: 0

Views

Author

Klaus Brockhaus, Feb 04 2002

Keywords

Comments

For an integer j not in A067030 there exists no integer k of the form m + reverse(m) such that j occurs in the trajectory of k. a(n) >= A067032(n); A067737 gives the terms of A067030 such that a(n) > A067032(n). A067288 gives the records in this sequence, A067287 gives the terms of A067030 at which these records are attained.

Examples

			a(14) = 5, since A067030(14) = 55 and the five integers 7, 23, 32, 41, 50 are not of the form m + reverse(m) for any m and 55 occurs in the trajectory of each of them. a(25) = 11, since A067030(25) = 154 and the eleven integers 1, 25, 34, 43, 52, 59, 61, 68, 70, 86, 95 are not of the form m + reverse(m) for any m and 154 occurs in the trajectory of each of them.
		

Crossrefs

A067287 n sets a new record for the number of integers k such that k is not of the form m + reverse(m) for any m and n occurs in the 'Reverse and Add' trajectory of k (cf. A067284).

Original entry on oeis.org

0, 22, 33, 44, 66, 88, 110, 121, 242, 484, 968, 1837, 2222, 3102, 4444, 4884, 7106, 8888, 12221, 24442, 44044, 48884, 88088, 176176, 293392, 295482, 466664, 597795, 688886, 711106, 797797, 930028, 933328, 997799, 1112111, 1197801, 1686861
Offset: 0

Views

Author

Klaus Brockhaus, Feb 04 2002

Keywords

Comments

A067288 gives the corresponding records.

Examples

			33 belongs to the sequence because three integers k (viz. 3, 21, 30) are not of the form j + reverse(j) for any j and 33 occurs in the "Reverse and Add!" trajectory of these k and for m < 33 there are at most two integers which have the corresponding property.
		

Crossrefs

Extensions

More terms from Larry Reeves (larryr(AT)acm.org), Dec 18 2002
Showing 1-2 of 2 results.