A065411 Fibonacci numbers whose digits sum to a square.

0, 1, 13, 144, 806515533049393, 61305790721611591, 83621143489848422977, 6356306993006846248183, 155576970220531065681649693, 78569350599398894027251472817058687522

Offset

1,3

Links

Harry J. Smith, Table of n, a(n) for n = 1..50

Example

144 is in the sequence because (1) it is a Fibonacci number and (2) the sum of its digits 1 + 4 + 4 = 9 is a square.

Mathematica

Select[Fibonacci[Range[0, 200]], IntegerQ[Sqrt[Total[IntegerDigits[#]]]]&]//Union (* Harvey P. Dale, Dec 18 2025 *)

Prog

(PARI) { for (n=0, 300, my(f=fibonacci(n)); if (n!=1 && issquare(sumdigits(f)), print1(f, ", ")) ) } \\ Luc Stevens (lms022(AT)yahoo.com), Apr 15 2006

Crossrefs

Cf. A000045.

Sequence in context: A072351 A134489 A064525 * A354466 A038492 A270579

Adjacent sequences: A065408 A065409 A065410 * A065412 A065413 A065414

Keyword

base,nonn

Author

Jason Earls, Nov 22 2001

Extensions

Entry revised by N. J. A. Sloane, Jul 23 2006

Status

approved