A362436 Write out the sequence of squares, 1, 4, 9, 16, ..., then starting with the 16, successively delete the digits of the triangular numbers 1, 3, 6, 10, ...

1, 4, 9, 6, 25, 6, 49, 4, 81, 0, 121, 144, 169, 196, 225, 256, 289, 324, 361, 400, 441, 484, 529, 576, 625, 676, 729, 784, 841, 900, 961, 1024, 1089, 16, 1225, 1296, 1369, 1444, 15, 1600, 1681, 1764, 1849, 1936, 2025, 2116, 2209, 2304, 2401, 2500, 2601, 2704, 9, 2916, 3025, 31, 3249, 3364, 3481, 3600, 3721, 3844, 3969, 4096

Offset

1,2

Comments

If the result is nonzero, omit any leading zeros.

References

GCHQ, The GCHQ Puzzle Book, Penguin, 2016. See page 50, Problem 95(b).

Links

Table of n, a(n) for n=1..64.

Example

Delete 1 from 16 to get 6, then delete the 3 from 36 to get 6, and so on.

Crossrefs

Sequence in context: A141553 A095065 A061207 * A140694 A152454 A287932

Adjacent sequences: A362433 A362434 A362435 * A362437 A362438 A362439

Keyword

nonn,base

Author

N. J. A. Sloane, Apr 21 2023

Status

approved