A048386 Numbers n such that replacing digits d in decimal expansion of n with d^2 yields a square.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 23, 43, 49, 61, 100, 122, 136, 148, 163, 200, 221, 244, 269, 300, 305, 366, 400, 481, 488, 500, 600, 629, 700, 800, 884, 900, 1105, 1127, 1222, 1241, 1281, 1438, 1522, 1641, 1805, 2300, 2405, 2722, 2966, 3203, 4205, 4300, 4402

Offset

1,3

Links

Table of n, a(n) for n=1..53.

Example

2722 = (2)(7)(2)(2) -> (4)(49)(4)(4) = 44944 = 212^2 and square.

Prog

(Magma) f:=func<n|StringToInteger(&cat[IntegerToString(h): h in Reverse([c^2: c in Intseq(n)])])>; [0] cat [k:k in [1..4500]|IsSquare(f(k))]; // Marius A. Burtea, Feb 13 2020

Crossrefs

Cf. A000290, A048385, A048387.

Sequence in context: A322516 A132080 A307636 * A302503 A198044 A133134

Adjacent sequences: A048383 A048384 A048385 * A048387 A048388 A048389

Keyword

nonn,base

Author

Patrick De Geest, Mar 15 1999

Status

approved