A262900 -id:A262900 - cp's OEIS frontend

A262901 Numbers that have at least one leaf-child in the tree generated by edge-relation A049820(child) = parent.

4, 5, 11, 14, 16, 17, 22, 27, 29, 32, 35, 41, 44, 46, 48, 51, 57, 58, 62, 65, 69, 70, 77, 80, 81, 91, 92, 96, 101, 102, 107, 110, 111, 114, 118, 119, 120, 128, 129, 130, 138, 139, 141, 144, 147, 148, 152, 155, 158, 161, 162, 165, 166, 169, 176, 181, 187, 191, 192, 199, 201, 214, 215, 216, 222, 224, 227, 231, 234, 238, 239, 247, 248, 249, 255, 258, 262, 264, 269, 277, 278, 282, 286, 291, 294, 296

Offset: 1

Antti Karttunen, Oct 06 2015

nonn

Positions of nonzeros in A262900.
Numbers n such that there is at least one k such that k - d(k) = n [where d(k) is the number of divisors of k, A000005(k)], but there is no such x that x - d(x) = k, in other words, k is one of the terms of A045765.
Sequence A262902 sorted into ascending order, with duplicates removed.

Antti Karttunen, Table of n, a(n) for n = 1..10000

Cf. A000005, A045765, A049820, A262900, A262902.
Cf. A262903 (a subsequence).
Subsequence of A236562.
Cf. also A257508.

A262903 Numbers that are not leaves but all of whose children are leaves in the tree generated by edge-relation A049820(child) = parent.

Original entry on oeis.org

4, 5, 14, 16, 32, 41, 44, 77, 80, 92, 101, 110, 119, 128, 139, 148, 158, 161, 169, 176, 191, 192, 199, 215, 224, 227, 234, 238, 249, 262, 264, 277, 296, 311, 317, 327, 350, 351, 352, 360, 363, 382, 385, 389, 392, 395, 396, 411, 427, 430, 437, 448, 449, 461, 464, 483, 488, 518, 523, 531, 532, 542, 552, 561, 568, 570, 577, 579, 600, 601, 613, 619, 632, 634, 636, 645, 648, 659, 665, 666, 671, 682, 683, 696, 705, 723

Offset: 1

Antti Karttunen, Oct 06 2015

nonn

Numbers n for which A060990(n) > 0 and A060990(n) = A262900(n).

Numbers n for which A262695(n) = 2.

Antti Karttunen, Table of n, a(n) for n = 1..10000

Cf. A000005, A049820, A060990, A262695, A262900.
Subsequence of A262901 and A236562.
No common terms with A259934.
Cf. also A257512.

cp's OEIS Frontend

A262901 Numbers that have at least one leaf-child in the tree generated by edge-relation A049820(child) = parent.

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