A326740 Numbers which converge to 7 under repeated application of the powertrain map of A133500.

7, 71, 75, 107, 117, 127, 137, 147, 157, 167, 177, 187, 197, 207, 307, 407, 507, 523, 543, 607, 707, 711, 723, 747, 751, 807, 907, 1071, 1075, 1171, 1175, 1271, 1275, 1371, 1375, 1471, 1475, 1571, 1575, 1671, 1675, 1771, 1775, 1871, 1875, 1971, 1975, 2071

Offset

1,1

Links

Table of n, a(n) for n=1..48.

Example

75 -> 7^5 = 16807 -> 1^6*8^0*7 = 7.

Crossrefs

Cf. A133500, A133501, A135384, A135385, A309385, A326733, A326734, A326735, A326736, A326737, A326738, A326739, A326741, A326742.

Sequence in context: A111462 A045713 A090155 * A107163 A179784 A142037

Adjacent sequences: A326737 A326738 A326739 * A326741 A326742 A326743

Keyword

nonn,base,easy

Author

Martin Renner, Jul 22 2019

Status

approved