A383291 Successively larger gaps in happy numbers start at this happy number.

1, 32, 49, 109, 139, 409, 496, 566, 3392, 4287, 5364, 358962, 488444, 4488044, 59299951, 59999665, 88889733, 488849933, 569199933, 5888999662, 3888899909932, 5799999799999999999999999999999999999999999860, 5799999999999997999999999999999999999999999860

Offset

1,2

Links

Rahid Zaman, Table of n, a(n) for n = 1..37

Shyam Sunder Gupta, Happy Numbers, Exploring the Beauty of Fascinating Numbers, Springer (2025) Ch. 7, 209-222.

Rahid Zaman, C++ program to compute a(n)

Example

1 and 7 are successive happy numbers and so the first gap is 6. 32 and 44 are successive happy numbers and this is the first gap larger than 6, so 32 is in the sequence as the succeeding term to 1.

Prog

(C++) // See the separate program file.

Crossrefs

Cf. A007770.

Sequence in context: A066472 A140172 A259765 * A256521 A037008 A383732

Adjacent sequences: A383288 A383289 A383290 * A383292 A383293 A383294

Keyword

nonn,base

Author

Shyam Sunder Gupta, Apr 22 2025

Extensions

a(21) from Amiram Eldar, Apr 26 2025

a(22)-a(37) from Rahid Zaman, Mar 06 2026

Status

approved